docs: fix 404 link

[panpan0000]

What does this PR do?

ISSUE:
when you go to doc : https://huggingface.co/docs/transformers/main/en/main_classes/trainer#specific-gpus-selection

the link is 404 due to URL is case sentitive.

Fixes # (issue)

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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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[amyeroberts]

Thanks for fixing!

[panpan0000]

@amyeroberts , Many thanks to your kindly review and help.

But the check was unsuccessful and I was lost.

detail log as below

but even I ran make quality on main head 06343b0 , it failed

Oh no! 💥 💔 💥
3 files would be reformatted, 2678 files would be left unchanged.

or run on my PR with command doc-builder style src/transformers docs/source --max_len 119 --check_only --path_to_docs docs/source, it was succesful.

[amyeroberts]

@panpan0000 Unfortunately we had some package dependency nightmares this week. The fix was pushed to main - I can see you've rebased to get the updates and it's all working now ❤️

Thank you for your patience and for looking into the issue. Once the final build PR documentation run has finished we can merge :)

[panpan0000]

awesome @amyeroberts , nice community here!