KieProjectDefaultClasspathTest.createMultpleJarAndFileResources() fails sometimes when run on IBM JDK

KieProjectDefaultClasspathTest.createMultpleJarAndFileResources() uses KieServicesEventListerner which is referenced as WeakReference in KieServicesImpl and ClasspathKieProject. IBM JDK handles garbage collection differently than Oracle JDK and sometimes frees the listener during test run so the test fails. The test should hold the reference to the listener during whole test run.