[TASK] Cleanup TestBase

We usually do not add inline @string annotations. Remove them.

Change-Id: Idf83dbfdc7fc092e5d70d4004e8c5093eb26f491
Resolves: #73878
Releases: master
Reviewed-on: https://review.typo3.org/47001


Reviewed-by: Andreas Fernandez <typo3@scripting-base.de>
Tested-by: Andreas Fernandez <typo3@scripting-base.de>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>