[TASK] Add functional tests for generic persistence

To backup the changes in Extbase's generic persistence,
we add some functional tests.

Resolves: #55661
Related: #55360
Related: #55167
Releases: 6.2
Change-Id: I0b845618b1cec9788ca36ac59e25ea6779f01cb6
Reviewed-on: https://review.typo3.org/28262
Reviewed-by: Marc Bastian Heinrichs
Tested-by: Marc Bastian Heinrichs
Reviewed-by: Steffen Ritter
Tested-by: Steffen Ritter