[BUGFIX] Option labels not translated anymore

The configuration options labels are not translated anymore
in the Extension Manger.

This is due to a recent refactoring, which encapsulated
the translation process in a separate method,
but forgot to return the translated value.

Resolves: #57198
Releases: 6.2
Change-Id: Ib0051225860c408b00827bf7212835beafbbd2fa
Reviewed-on: https://review.typo3.org/28657
Reviewed-by: Georg Ringer
Tested-by: Georg Ringer