refactor(firebase_performance): use firebase.google.com link for `h…

…omepage` in `pubspec.yaml` (#8737)

Co-authored-by: Russell Wheatley <russellwheatley85@gmail.com>

packages/firebase_performance/firebase_performance/pubspec.yaml

@@ -3,8 +3,8 @@ description:
   Flutter plugin for Google Performance Monitoring for Firebase, an app
   measurement solution that monitors traces and HTTP/S network requests on Android and
   iOS.
-homepage: https://firebase.flutter.dev/docs/performance/overview
-repository: https://github.com/firebase/flutterfire/tree/master/packages/firebase_performance
+homepage: https://firebase.google.com/docs/perf-mon
+repository: https://github.com/firebase/flutterfire/tree/master/packages/firebase_performance/firebase_performance
 version: 0.8.0+13
 
 false_secrets: