[doc] Fix some docstrings in src/diffusers/training_utils.py

[mreraser]

What does this PR do?

Fixes #9567

• put function explanation before "Args"
• correct indentation

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• 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?

Who can review?

Hello @a-r-r-o-w, @yiyixuxu, and @stevhliu! May I kindly ask for your review? (or anyone who wants to review)

I would greatly appreciate it if anyone who is available could take some time to look it over.

Thank you in advance for your time and assistance!

[HuggingFaceDocBuilderDev]

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[stevhliu]

Nice! You can run make style to apply automatic style corrections to fix the failing CI test :)

[mreraser]

Nice! You can run make style to apply automatic style corrections to fix the failing CI test :)

Thank you for the guidance @stevhliu ! 🙌 I ran make style. Really appreciate your help!

[a-r-r-o-w]

@sayakpaul Do you know why we're having the documentation test fails? It is unrelated to the changes in PR and seems like an environment problem

[sayakpaul]

@a-r-r-o-w check this internal link: https://huggingface.slack.com/archives/C041M7M98JV/p1728573992392519

[a-r-r-o-w]

oh okay. can we merge PRs in the meantime or do we wait until fixed? i think there were a few merges earlier so should be good i guess?

[sayakpaul]

Yes we can merge before!

[a-r-r-o-w]

thanks!