fix(auth): correct modular AuthListenerCallback type (#8436)

Author: DoctorJohn

packages/auth/lib/modular/index.d.ts

@@ -16,7 +16,7 @@
  */
 
 import { ReactNativeFirebase } from '@react-native-firebase/app';
-import { FirebaseAuthTypes, CallbackOrObserver, AuthListenerCallback } from '../index';
+import { FirebaseAuthTypes, CallbackOrObserver } from '../index';
 import { firebase } from '..';
 
 import Auth = FirebaseAuthTypes.Module;
@@ -182,7 +182,7 @@ export function isSignInWithEmailLink(auth: Auth, emailLink: string): boolean;
  */
 export function onAuthStateChanged(
   auth: Auth,
-  nextOrObserver: CallbackOrObserver<AuthListenerCallback>,
+  nextOrObserver: CallbackOrObserver<FirebaseAuthTypes.AuthListenerCallback>,
 ): () => void;
 
 /**
@@ -194,7 +194,7 @@ export function onAuthStateChanged(
  */
 export function onIdTokenChanged(
   auth: Auth,
-  nextOrObserver: CallbackOrObserver<AuthListenerCallback>,
+  nextOrObserver: CallbackOrObserver<FirebaseAuthTypes.AuthListenerCallback>,
 ): () => void;
 
 /**

packages/auth/type-test.ts

@@ -1,5 +1,5 @@
 // import firebase from '@react-native-firebase/app';
-import firebase, { FirebaseAuthTypes, signInWithPhoneNumber } from '.';
+import firebase, { FirebaseAuthTypes, onAuthStateChanged, signInWithPhoneNumber} from '.';
 
 console.log(firebase.default().currentUser);
 
@@ -55,4 +55,5 @@ firebase.auth().signInAnonymously().then();
 firebase.auth().signInWithEmailAndPassword('', '').then();
 
 // Verify Modular API
+onAuthStateChanged(firebase.auth(), user => console.log(user));
 signInWithPhoneNumber(firebase.auth(), '+1234567890');