docs(helpers/toc): max_items option >=7.3.0

[KentarouTakeda]

Added documentation for new option max_items in the hexojs/hexo#5487 toc() helper.

ja is not yet integrated with Crowdin, so I translated it in this pull request.

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Check List

Please read and check followings before submitting a PR.

• Others (Update, fix, translation, etc...)
  • Languages:
  • en English
  • ru Russian
  • zh-cn simplified Chinese
  • zh-tw traditional Chinese
  • ja Japanese

[github-actions]

Theme thumbnails validation completed.

[uiolee]

Thank you for your contribution.

We are doing translation work on crowdin, you don’t need to translate it in git.
Just add English content to the github, and then translate it in crowdin after PR was merged.

[KentarouTakeda]

I removed ja translation.

Just add English content to the github, and then translate it in crowdin after PR was merged.

Sure, but it seems that ja is not integrated to Crowdin yet.

ja is not yet integrated with Crowdin, so I translated it in this pull request.

[uiolee]

My bad. Now ja has been added

[KentarouTakeda]

Thanks, confirmed!

[KentarouTakeda]

I've submited japanese translation to crowdin.