Set thread as a daemon is the thread factory in order to avoid blocki…

…ng main thread

nopol/src/main/java/xxl/java/junit/CustomClassLoaderThreadFactory.java

@@ -12,6 +12,7 @@ public CustomClassLoaderThreadFactory(ClassLoader customClassLoader) {
     @Override
     public Thread newThread(Runnable r) {
         Thread newThread = Executors.defaultThreadFactory().newThread(r);
+        newThread.setDaemon(true); // use to avoid a main process to continue running waiting for this thread end at the end of execution
         newThread.setContextClassLoader(customClassLoader());
         return newThread;
     }