CustomCDIProviderTest based on incorrect assumption

They way javax.enterprise.inject.spi.CDI works is that each time the current() method is called, the CDI class invokes CDIProvider.getCDI() to retrieve a (possibly new) CDI instance.

org.jboss.cdi.tck.tests.lookup.manager.provider.custom.ForwardingCDIProvider works with an assumption that it is safe to take a single CDI instance and always return it wrapped. However, a custom CDIProvider may be returning different CDI instances in different contexts (e.g. for different application). Therefore, the way ForwardingCDIProvider is currently implemented may cause failures in tests that follow CustomCDIProviderTest if the CDI implementation uses these context-sensitive CDI instances