Revert "[TASK] Make current persistence replaceable"

This reverts commit 4d4b047e8eca2cfd86eef94954066f292277394f.

Conflicts:
	Classes/Persistence/Generic/PersistenceManager.php
	Tests/Unit/Persistence/RepositoryTest.php

Resolves: #46837
Releases: 6.1
Change-Id: I87914c6786d75ce217993cb6a70721b821bd0647
Reviewed-on: https://review.typo3.org/19488
Reviewed-by: Alexander Schnitzler
Tested-by: Alexander Schnitzler