Also, remove obsolete Fixture functions.

Used command(s):

> ./Build/Scripts/runTests.sh -s phpstanGenerateBaseline

Resolves: #98749
Related: #87607
Releases: main
Change-Id: Ifc75db8d3fcda52d22d47292b43b250de255cd25
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/76432


Tested-by: core-ci <typo3@b13.com>
Tested-by: Kevin Appelt <kevin.appelt@icloud.com>
Tested-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Kevin Appelt <kevin.appelt@icloud.com>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>