[Translate] Add Korean [ko_KR]

[ignotus666]

@MarongHappy could you confirm that you would like us to add the files to translate the website into Korean?

[github-actions]

• The .po files have been created for ko_KR and are now available on Weblate. If you prefer not to use Weblate and intend to submit translations via a Pull Request, your language files can be found on the next-release branch in _translator-files/po/ko_KR/.
• Please consult this README file for more information on the translation process.

[ann0see]

As soon as we have a translator, the create translation issues script needs to be updated.

[ann0see]

Related to: #854

[ignotus666]

Wow, I failed to adhere to the instructions I created myself... (adding the language code in square brackets). Thanks @ann0see : )

[ignotus666]

This person hasn't surfaced here, but they've already started ploughing through the Korean translations on Weblate, so I think it's safe to add them to the translator's list.

[ann0see]

As Korean will go live soon, closing