SpringBoot Upgrade to JUnit Jupiter 5.13.1

Upgrade to JUnit Jupiter 5.13.1.

Comment From: snicoll

This unfortunately isn't an easy upgrade. Our use of @ClassPathExclusions are broken. If tests are invoked in isolation it works but failed before the second test execution:

 org.junit.platform.commons.PreconditionViolationException: Cannot create Launcher without at least one TestEngine; consider adding an engine implementation JAR to the classpath

Other extensions that are invoking tests are broken in a similar fashion. https://github.com/snicoll/spring-boot/commit/65014d9524a61bd0841cfe99ead47c27a904e2ec reproduces it

Comment From: wilkinsona

Our custom class loader is being closed due to https://github.com/junit-team/junit-framework/commit/1d818398e9c51cb2fe471eae84277c207dd62ffb. Once closed, it can't load anything so the META-INF/services entry for the test engine isn't found.