Work towards fixing Flax tests
Author: avital
Pull request: yes

I still get failures that seem due to missing HTTP artifacts, e.g.

E               OSError: Can't load weights for 'roberta-large'. Make sure that:
E
E               - 'roberta-large' is a correct model identifier listed on 'https://huggingface.co/models'
E
E               - or 'roberta-large' is the correct path to a directory containing a file named pytorch_model.bin.

This is the command I used to run tests:

    RUN_SLOW=true python -m pytest -k flax -n 8 --dist=loadfile -rA -s --make-reports=tests_flax ./tests/ | tee tests_output.txt

# What does this PR do?

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Fixes # (issue)


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Comments:
/cc @patrickvonplaten for review

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/master/CONTRIBUTING.md) are likely to be ignored.

Think this issue has been resolved :-)

Yes :)