Update ApplicationWrapper param that received null value to Nullable

Summary:
Runtime plugin showed null savedInstanceState passed into onActivityCreated.

## Context
We are in the process of making the entire codebase Nullsafe. This diff relies on a runtime codemod to track when null is passed into a parameter that is not marked as Nullable in java. Based on runtime data, we can be 100% certain that this parameter needs to be Nullable

Reviewed By: jocelynluizzi13

Differential Revision: D60469755

fbshipit-source-id: 2d4385326bff7c4f75c1c26afd2552d2be4fa42b

android/src/main/java/com/facebook/flipper/plugins/inspector/ApplicationWrapper.java

@@ -20,6 +20,7 @@
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
+import javax.annotation.Nullable;
 
 public class ApplicationWrapper implements Application.ActivityLifecycleCallbacks {
 
@@ -47,7 +48,7 @@ public ApplicationWrapper(Application application) {
   }
 
   @Override
-  public void onActivityCreated(Activity activity, Bundle savedInstanceState) {
+  public void onActivityCreated(Activity activity, @Nullable Bundle savedInstanceState) {
     mActivities.add(new WeakReference<>(activity));
     notifyListener();
   }