Merge pull request #872 from OneSignal/fix_flaky_waiting_of_threads_in_tests

Add a 2nd run of runOSThreads if first didn't find

Author: jkasten2

OneSignalSDK/unittest/src/test/java/com/test/onesignal/TestHelpers.java

@@ -173,7 +173,8 @@ static void threadAndTaskWait() throws Exception {
 
       boolean createdNewThread;
       do {
-         createdNewThread = runOSThreads();
+         // We run a 2nd time if we did not find any threads to ensure we don't skip any
+         createdNewThread = runOSThreads() || runOSThreads();
 
          boolean advancedRunnables = OneSignalPackagePrivateHelper.runAllNetworkRunnables();
          advancedRunnables = OneSignalPackagePrivateHelper.runFocusRunnables() || advancedRunnables;