In-framework deployment NeMo 2.0 nemo_export.py test
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beep boop 🤖: 🙏 The following files have warnings. In case you are familiar with these, please try helping us to improve the code base.

---

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

```
************* Module nemo.deploy.nlp.megatronllm_deployable
nemo/deploy/nlp/megatronllm_deployable.py:53:0: C0116: Missing function or method docstring (missing-function-docstring)
nemo/deploy/nlp/megatronllm_deployable.py:103:4: C0116: Missing function or method docstring (missing-function-docstring)
nemo/deploy/nlp/megatronllm_deployable.py:446:4: C0116: Missing function or method docstring (missing-function-docstring)
************* Module nemo.deploy.nlp.query_llm
nemo/deploy/nlp/query_llm.py:29:0: C0115: Missing class docstring (missing-class-docstring)
************* Module setup
setup.py:57:0: C0116: Missing function or method docstring (missing-function-docstring)
setup.py:131:0: C0115: Missing class docstring (missing-class-docstring)
setup.py:20:0: W0611: Unused import codecs (unused-import)

-----------------------------------
Your code has been rated at 9.83/10
```

---

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* Add sensible and useful docstrings to functions and methods
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Thank you for improving NeMo's documentation! [🤖]: Hi @janekl 👋,

We wanted to let you know that a [CICD pipeline](https://github.com/NVIDIA/NeMo/actions/runs/12713097491) for this PR just finished successfully

So it might be time to merge this PR or get some approvals

I'm just a bot so I'll leave it you what to do next.

//cc @pablo-garay @ko3n1g
# What does this PR do ?

Adding `nemo_export.py --in-framework True [...]` test in Github Actions. This also includes:
* adding NeMo 2.0 support in this script
* adding [`generate`](https://github.com/NVIDIA/NeMo/blob/3e5fb000ab55071b0685be9986f25eb7e0a2697e/nemo/deploy/nlp/megatronllm_deployable.py#L182) method  for `MegatronLLMDeployableNemo2` for parity with NeMo 1.0 [`generate`](https://github.com/NVIDIA/NeMo/blob/84b2bf0989a1cfde0258acb5804cd5bdcd357449/nemo/deploy/nlp/megatronllm_deployable.py#L396) for `MegatronLLMDeployable`
* script to generate a Lambada-like dataset (5 samples) plus several minor bugfixes

**Collection**: NLP/ LLM

# Usage

See edits in `.github/workflows/cicd-main.yml`.

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# Before your PR is "Ready for review"
**Pre checks**:
- [x] Make sure you read and followed [Contributor guidelines](https://github.com/NVIDIA/NeMo/blob/main/CONTRIBUTING.md)
- [x] Did you write any new necessary tests?
- [ ] Did you add or update any necessary documentation?
- [ ] Does the PR affect components that are optional to install? (Ex: Numba, Pynini, Apex etc)
  - [ ] Reviewer: Does the PR have correct import guards for all optional libraries?
  
**PR Type**:
- [ ] New Feature
- [x] Bugfix
- [ ] Documentation

If you haven't finished some of the above items you can still open "Draft" PR.


## Who can review?

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[Contributor guidelines](https://github.com/NVIDIA/NeMo/blob/main/CONTRIBUTING.md) contains specific people who can review PRs to various areas.

# Additional Information
* Related to # (issue)
