[TASK] Class Loader optimisation

* Skip cache->has() calls
* Remove class alias registration on object instantiation

Resolves: #55037
Releases: 6.2
Change-Id: Ia9f8523a9d710b2703c3ee2caf2f1fa9ae6e76e9
Reviewed-on: https://review.typo3.org/26836
Reviewed-by: Markus Klein
Reviewed-by: Thomas Maroschik
Reviewed-by: Helmut Hummel
Tested-by: Helmut Hummel