[BUGFIX] Avoid 4th argument on GU::callUserFunction() in test

GeneralUtility::callUserFunction() has only three
parameters, as detected by phpstan.

Resolves: #103923
Releases: main, 12.4
Change-Id: I31fc48f343558dd2e0d73feeb3933e249fa625a4
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/84410


Tested-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: core-ci <typo3@b13.com>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>