Spring Ensure CompileWithTargetClassAccessExtension only uses the Jupiter TestEngine

Commit 9dd7f5412aa72efdeb1ba15b2cd86c6391540b61 addressed the issue of having the TestNG TestEngine for the JUnit Platform (JUnit 5) on the test runtime classpath by allowing org.testng types to pass through to the original ClassLoader; however, that fix merely obfuscates the underlying issue.

The underlying issue is that the CompileWithTargetClassAccessExtension is only applicable to JUnit Jupiter tests and therefore should launch the JUnit Platform with only the JUnit Jupiter TestEngine active.