Fixed app open on cold start from notification

* Main activity wasn't luanching when tapping on a notification that
resulted in the app being cold started.
* This was fixed by adding a missing startActivity and removing an
unneeded PendingIntent
* This was a bug interduced in PR #1192 in 4.0.0 release

Author: jkasten2

OneSignalSDK/onesignal/src/main/java/com/onesignal/OneSignal.java

@@ -2178,10 +2178,11 @@ static boolean startOrResumeApp(Activity inContext) {
             inContext.startActivity(launchIntent);
          } else {
             launchIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
-            PendingIntent.getActivity(inContext, 0, launchIntent, 0);
+            inContext.startActivity(launchIntent);
          }
          return true;
       }
+
       return false;
    }