clearer model variable naming: blenderbot
# What does this PR do?
clearer model variable naming: blenderbot

<img width="1512" alt="Ekran Resmi 2022-03-16 15 12 18" src="https://user-images.githubusercontent.com/58150504/158587347-5934dc62-b07e-4fa1-b49a-5f3be4b0f250.png">

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

## Who can review?
@gante 

_The documentation is not available anymore as the PR was closed or merged._