update translations for v2023.4

[sadiqkhoja]

Progress toward #823. We'll pull translations again right before release.

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[sadiqkhoja]

I don't know why locale/ja.json is not updated?

[matthew-white]

I don't think there's been much translation of Japanese lately, which would explain why there aren't new translations in ja.json. A few messages have been changed or removed in en.json5 as part of .4, and if they were previously translated, you'd expect to see them removed in ja.json. But it could be that they just weren't translated to begin with.