Backport translations to v1.21

[denyskon]

I manually fixed most of the files so that used translation keys don't get deleted.

[lunny]

Have you generated them via build/backport-locale.go ?

[denyskon]

I first tried, but for some reason the output of that command produced a lot of unnecessary spacing and quotation changes which according to the feedback in previous PRs may break everything, so I ended up doing it manually.

[wxiaoguang]

which according to the feedback in previous PRs may break everything

That's impossible. The generated ini should be able to be loaded correctly.

[denyskon]

All backticks are replaced by double quotes. If that's okay I can redo it using the script, however I don't see a reason why.

[wxiaoguang]

All backticks are replaced by double quotes. If that's okay I can redo it using the script, however I don't see a reason why.

Crowdin doesn't recognize backticks. key = ` value` then Crowdin treats it as key = "` value`".

The legacy INI package only uses backticks when it is necessary, so key = ` val` will become key = " val" when it saves the INI to a file.

[denyskon]

Alright, so I now did it using the tool