[TASK] Make use of .t3-table in EXT: beuser *compare

Use <table class="t3-table"> in backend module compare view.

Change-Id: Icd8fb361a61c6bbfd933fc4b1b011838f18868e8
Resolves: #55139
Releases: 6.2
Reviewed-on: https://review.typo3.org/26929
Reviewed-by: Marcin S?gol
Tested-by: Marcin S?gol
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters