Updates for file app/assets/locales/en.json in ja (#5572)

* Translate app/assets/locales/en.json in ja

100% translated source file: 'app/assets/locales/en.json'
on 'ja'.

* Translate app/assets/locales/en.json in ja

100% translated source file: 'app/assets/locales/en.json'
on 'ja'.

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Co-authored-by: transifex-integration[bot] <43880903+transifex-integration[bot]@users.noreply.github.com>