Restore the readme change.

Author: jonsimantov

release_build_files/readme.md

@@ -677,6 +677,7 @@ code.
 ## Release Notes
 ### Upcoming Release
 -   Changes
+    - Auth: Removed deprecated `User::UpdateEmail` method.
     - iOS: Added an option to explicitly specify your app's `AppDelegate` class
       name via the `FirebaseAppDelegateClassName` key in `Info.plist`. This
       provides a more direct way for Firebase to interact with your specified