[Wi-Fi] Fix AddAppNetworksFragmentTest one unit test failed case

onDestroy_quitWorkerThread in AddAppNetworksFragmentTest failed due to java.lang.IllegalStateException: no event down from INITIALIZED
Solution: Initialize fragment before calling the onDestroy API.

Bug: 151696220
Test: make RunSettingsRoboTests ROBOTEST_FILTER=AddAppNetworksFragmentTest
Change-Id: I80d28c6e7490a36a7ff26313d30d33b2f7d727c1

tests/robotests/src/com/android/settings/wifi/addappnetworks/AddAppNetworksFragmentTest.java

@@ -265,6 +265,9 @@ public class AddAppNetworksFragmentTest {
 
     @Test
     public void onDestroy_quitWorkerThread() {
+        addOneSpecifiedRegularNetworkSuggestion(mNewWpaSuggestionEntry);
+        setUpBundle(mFakedSpecifiedNetworksList);
+        setupFragment();
         mAddAppNetworksFragment.mWorkerThread = mock(HandlerThread.class);
 
         try {