[TASK] Fix CGL violations against ClassDocComment

Some violations against the ClassDocComment was
found in the UnitTests.

Change-Id: I55e4c1b21635d9ff905b1d9e6685dd1498c03aca
Fixes: #38738
Releases: 6.0
Reviewed-on: http://review.typo3.org/12700
Reviewed-by: Philipp Gampe
Reviewed-by: Oliver Klee
Reviewed-by: Helmut Hummel
Tested-by: Helmut Hummel