Unify HF converter scripts and arguments
jenkins jenkins jenkins jenkins jenkins jenkins Looks good, these scripts look much better now. Some minor remarks:
* I often do CTRL+F on some arguments like, for example, `in_file`. For the current style like `parser.add_argument("--in-file", ...)` -- dash vs underscore -- such searches won't work for argument definitions which is sometimes inconvenient.
* For StarCoder I think we have [a standalone config](https://github.com/NVIDIA/NeMo/blob/main/examples/nlp/language_modeling/conf/megatron_starcoder_config.yaml) now so can we change default for `--hparams-file` to that? Maybe @dimapihtar could additionally confirm
* Maybe we can drop size param = `7b` for Mistral conversion files to further unify names? This one comes only in one flavor anyway
* I would pass all arguments to `load_config` explicitely rather than with `args` unless it's really inconvenient / inflexible (but it's up to you)
* In some cases we could use `load_state_dict_helper` or `torch_dtype_from_precision` util functions from nemo/collections/nlp/parts/utils_funcs.py @janekl  Thanks for the comments.
I changed 1 - dash to underscore
For the rest, I don't have BW to change and verify all atm. We can proceed to ask the original PICs to update them in the following PR. jenkins
# What does this PR do ?

Unify HF converter scripts and arguments


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