Cleanup: Remove not used SystemClassLoaderUnsafe #413

Job	Run time
Swift tests (swift:6.0.2 jdk:Corretto os:jammy)	4m 12s
Verify Samples (swift:6.0.2 jdk:Corretto os:jammy)	17m 17s
Java tests (swift:6.0.2 jdk:Corretto os:jammy)	8m 52s
soundness / Format check	0s
soundness / Documentation check	40s
soundness / API breakage check	0s
soundness / Broken symlinks check	4s
soundness / License headers check	9s
soundness / Python lint check	5s
soundness / Shell check	31s
soundness / Unacceptable language check	2s
soundness / YAML lint check	3s
	31m 55s

Provide feedback