[BUGFIX] Select correct database table in BackendUserAuthentication::writelog

Change-Id: I8877a68d5de5017346179368dab8002d8f08077f
Resolves: #77683
Releases: master
Reviewed-on: https://review.typo3.org/49640


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