[Fix] Add missing localizations to locale/uk/

[vsemozhetbyt]

Refs: #1737

[ghost]

Suggestions：
After modification, please run：

1）npm run build
2）npm run test
3）npm run start

Then go to http://localhost:8080/uk and you'll see what you want by clicking pages.

[vsemozhetbyt]

I've added more missing localizations.

[vsemozhetbyt]

http://localhost:8080/uk seems OK.

[ghost]

There seems to be ONLY ONE left for you to translate in this file:
/locale/uk/download/index.md

[vsemozhetbyt]

I've added some more translations in the /locale/uk/download/index.md.

[ghost]

Thanks anyway!