doctest for BART and IBERT
# What does this PR do?

Adds BART and IBERT to the doc tests.
The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/transformers/pr_16459). All of your documentation changes will be reflected on that endpoint.<|||||>Hi @ydshieh  , I would need your help to move forward in my case <|||||>Hi, @abdouaziz 

Sorry for the late response. The Bart model is in fact already done by our internal developer.
Could you revert your change on the Bart model, please? 

Regarding iBERT, I will review later. Don't hesitate to drop a comment if you get any problem.

Apologies for this situation 🙏<|||||>This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

Please note that issues that do not follow the [contributing guidelines](https://github.com/huggingface/transformers/blob/main/CONTRIBUTING.md) are likely to be ignored.