[BUGFIX] Ensure BE_USER uid is always used as int

Fix some left-over places where an int-cast
is possibly necessary to avoid PHP warnings.

Resolves: #100866
Releases: main, 12.4, 11.5
Change-Id: If9111e0c2e2de8c90a94202cf518abdbe8c987fb
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/79036


Tested-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: core-ci <typo3@b13.com>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>