Fix nemo 1 packed sequence TE version error
Is this a safe hacking? wouldn't this impact functionality if you override `cu_seqlens_unpadded`? > Is this a safe hacking? wouldn't this impact functionality if you override `cu_seqlens_unpadded`?

Tested in the case of CP=1 this is fine.  Not confident about CP>1. Do you have suggestions on how to tackle CP>1? I am thinking shouldn't we fix `PackedSeqParams` in NeMo2.0 and make it same as NeMo1.0 ?
@tomlifu , I remember you tested `cu_seqlens_unpadded != cu_seqlens` with TE < 1.13? Yes, I tested cu_seqlens_unpadded != cu_seqlens with TE < 1.13 and it works. I don't think I used TE 1.13 at all. > I am thinking shouldn't we fix `PackedSeqParams` in NeMo2.0 and make it same as NeMo1.0 ?

Certainly. The current PR just fixes a bug in nemo 1. We will propagate the change to nemo 2 in a future PR.
 <!-- pylint-output-strict-mode-false -->

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---

Your code was analyzed with PyLint. The following annotations have been identified:

```
************* Module nemo.collections.nlp.models.language_modeling.megatron_gpt_model
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nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:374:0: C0301: Line too long (136/119) (line-too-long)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:420:0: C0301: Line too long (126/119) (line-too-long)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:467:0: C0301: Line too long (122/119) (line-too-long)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:801:0: C0301: Line too long (131/119) (line-too-long)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1116:0: C0301: Line too long (146/119) (line-too-long)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1137:0: C0301: Line too long (168/119) (line-too-long)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1347:0: C0301: Line too long (122/119) (line-too-long)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1398:0: C0301: Line too long (122/119) (line-too-long)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1455:0: C0301: Line too long (140/119) (line-too-long)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1637:0: C0301: Line too long (132/119) (line-too-long)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1638:0: C0301: Line too long (136/119) (line-too-long)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1640:0: C0301: Line too long (159/119) (line-too-long)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1812:0: C0301: Line too long (128/119) (line-too-long)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1832:0: C0301: Line too long (140/119) (line-too-long)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1840:0: C0301: Line too long (155/119) (line-too-long)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1861:0: C0301: Line too long (141/119) (line-too-long)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1931:0: C0301: Line too long (125/119) (line-too-long)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1958:0: C0301: Line too long (134/119) (line-too-long)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:141:0: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:154:0: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:180:0: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:199:0: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:252:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:290:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:294:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:306:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:314:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:476:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:479:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:711:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:715:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:797:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1114:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1187:12: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1236:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1265:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1468:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1604:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1612:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1621:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:1906:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:2059:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:2066:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:2072:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:20:0: W0611: Unused fields imported from dataclasses (unused-import)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:28:0: W0611: Unused _DataFetcherWrapper imported from lightning.pytorch.loops.fetchers (unused-import)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:30:0: W0611: Unused OmegaConf imported from omegaconf (unused-import)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:72:0: W0611: Unused activation_to_func imported from nemo.collections.nlp.parts.utils_funcs (unused-import)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:81:4: W0611: Unused megatron.core imported as core (unused-import)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:82:4: W0611: Unused tensor_parallel imported from megatron.core (unused-import)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:101:4: W0611: Unused init_method_normal imported from megatron.core.utils (unused-import)
nemo/collections/nlp/models/language_modeling/megatron_gpt_model.py:101:4: W0611: Unused scaled_init_method_normal imported from megatron.core.utils (unused-import)

-----------------------------------
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# What does this PR do ?

Adds a te version guard for packed sequence in NeMo 1 (NeMo 2 is unaffected)
Changes in #10688 should be paired with TE version >1.3
https://github.com/NVIDIA/TransformerEngine/blob/3d63cbb469ace2d1ad7798a956e16dee42bd655b/transformer_engine/pytorch/attention.py#L8179-L8185

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