Add line break after header (#1089)

Author: SUPERCILEX

auth/README.md

@@ -369,6 +369,7 @@ see the Firebase Auth documentation to
 and [register an AuthStateListener](https://firebase.google.com/docs/reference/android/com/google/firebase/auth/FirebaseAuth.html#addAuthStateListener(com.google.firebase.auth.FirebaseAuth.AuthStateListener)).
 
 #### ID tokens
+
 To retrieve the ID token that the IDP returned, you can extract an `IdpResponse` from the result
 Intent.