Update docstring for CLIPConfig

[yingzha]

What does this PR do?

Fixes missing imports in CLIPConfig docstring.

Before submitting

• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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• Did you write any new necessary tests?

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[HuggingFaceDocBuilderDev]

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

[stevhliu]

Thanks for the fix! Pinging @sgugger for a final look :)

Not sure what's happening with the failing circleci check. Could you try refreshing your permissions as shown here?

[sgugger]

Yes, you will need to refresh your circleCI permissions and push an empty commit so we can check the tests are passing.

[yingzha]

@sgugger Done.

[sgugger]

Thanks a lot!