[TASK] Use correct input type for backend user name search

Resolves: #102740
Releases: main
Change-Id: I353e2110935de792bda454705a5bc3e6ab1b2553
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/82296


Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: Oliver Bartsch <bo@cedev.de>
Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Reviewed-by: Oliver Bartsch <bo@cedev.de>
Tested-by: core-ci <typo3@b13.com>