[BUGFIX] Resolve itemsProcFunc in BackendUtility label functions

A couple of BackendUtility methods dealing with resolving
labels do now also evaluate a configured `itemsProcFunc`
to properly resolve the corresponding labels.

Resolves: #100855
Resolves: #102616
Releases: main, 12.4
Change-Id: Ic4efe1cc2a68e7ee938ca994649e074ddbba0819
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/82118


Tested-by: Oliver Bartsch <bo@cedev.de>
Tested-by: core-ci <typo3@b13.com>
Reviewed-by: Oliver Bartsch <bo@cedev.de>