[Nemo1] Generate sharded optimizer state dicts only if needed for saving
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Your code was analyzed with PyLint. The following annotations have been identified:

```
************* Module nemo.collections.nlp.parts.nlp_overrides
nemo/collections/nlp/parts/nlp_overrides.py:212:0: C0301: Line too long (140/119) (line-too-long)
nemo/collections/nlp/parts/nlp_overrides.py:217:0: C0301: Line too long (149/119) (line-too-long)
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nemo/collections/nlp/parts/nlp_overrides.py:425:4: C0116: Missing function or method docstring (missing-function-docstring)
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nemo/collections/nlp/parts/nlp_overrides.py:618:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/parts/nlp_overrides.py:637:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/parts/nlp_overrides.py:878:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/parts/nlp_overrides.py:997:0: C0115: Missing class docstring (missing-class-docstring)
nemo/collections/nlp/parts/nlp_overrides.py:1686:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/parts/nlp_overrides.py:1774:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/collections/nlp/parts/nlp_overrides.py:18:0: W0611: Unused import re (unused-import)
nemo/collections/nlp/parts/nlp_overrides.py:106:4: W0611: Unused tensorstore imported from megatron.core.dist_checkpointing.strategies (unused-import)

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Your code has been rated at 9.69/10
```

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Thank you for improving NeMo's documentation! > LGTM. should not functionally change ckpt content, just perf improvement correct?

That's correct. The ckpt contents are the same, and this is strictly a perf improvement
# What does this PR do ?
If not saving optimizers in the checkpoint, don't generate the sharded optimizer state dict, as it will ultimately be discarded. The ckpt contents are the same, and this is strictly a perf improvement

**Collection**: NLP

# Changelog 

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```

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