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# What does this PR do?
Update guidance docs to reflect grammar support in API. The previous
wording was vague and made it sound like openai API supported the
grammar parameter.


https://github.com/huggingface/text-generation-inference/blob/main/router/src/server.rs#L654
confirms that support for grammar is TGI only at this time.

## Before submitting
- [ x] This PR fixes a typo or improves the docs (you can dismiss the
other checks if that's the case).
- [x ] Did you read the [contributor
guideline](https://github.com/huggingface/transformers/blob/main/CONTRIBUTING.md#start-contributing-pull-requests),
      Pull Request section?
- [ x] Was this discussed/approved via a Github issue or the
[forum](https://discuss.huggingface.co/)? Please add a link
      to it if that's the case.
- [ x] Did you make sure to update the documentation with your changes?
Here are the
[documentation
guidelines](https://github.com/huggingface/transformers/tree/main/docs),
and
[here are tips on formatting
docstrings](https://github.com/huggingface/transformers/tree/main/docs#writing-source-documentation).
- [ x] Did you write any new necessary tests?


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