Japanese docs

[isamu-isozaki]

What does this PR do?

Adds Japanese documentations

Fixes #5285

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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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Since, it's the docs, also @stevhliu and @yiyixuxu

[stevhliu]

Nice work! 👏

You'll also need to modify the build_documentation.yml and build_pr_documentation.yml file to include the language code for Japanese (ja) to build the docs.

[isamu-isozaki]

@stevhliu Thanks for the review! And should be fixed

[stevhliu]

Thanks for the changes, just two minor ones remaining :)

[HuggingFaceDocBuilderDev]

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

[isamu-isozaki]

@stevhliu Forgot to say but should be done! Fixed the folder name to jp->ja too

[stevhliu]

Thanks again for your contribution! 🤗