[TASK] Streamline buttons in BE user module

Resolves: #71033
Releases: master
Change-Id: Ic7871987aeb6c6170e2e966880c5e370b1e703c5
Reviewed-on: https://review.typo3.org/44285


Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Reviewed-by: Andreas Fernandez <typo3@scripting-base.de>
Tested-by: Andreas Fernandez <typo3@scripting-base.de>