[TASK] Turn redis cache backend unit into functional tests

Our unit tests should not rely on running daemons, there is
a functional test environment to take care of this. The patch
turns redis cache backend unit tests into funcitional tests
and adapts the unit test setup to no longer start dependencies.

Resolves: #85565
Releases: master
Change-Id: I8d81209ed339d35af11bb06fb7cb191845b6b587
Reviewed-on: https://review.typo3.org/57607


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>