Fixing method name

Author: lostintangent

android/app/src/main/java/com/microsoft/codepush/react/CodePush.java

@@ -396,7 +396,7 @@ private void loadBundle() {
             try {
                 // #1) Get the private ReactInstanceManager, which is what includes
                 //     the logic to reload the current React context.
-                Field instanceManagerField = ReactActivity.class.getDeclaredField("mReacInstanceManager");
+                Field instanceManagerField = ReactActivity.class.getDeclaredField("mReactInstanceManager");
                 instanceManagerField.setAccessible(true); // Make a private field accessible
                 final Object instanceManager = instanceManagerField.get(mainActivity);