Add firebase config for each flavor

[amaury901130]

Description

• Add firebase config for each flavor.

1- Create a firebase project 2- SetUp the configuration for each flavor:

await Firebase.initializeApp(
    options: const FirebaseOptions(
      apiKey: "your_key",
      authDomain: "your_auth_domain.firebaseapp.com",
      databaseURL: "https://your_db_url.firebaseio.com",
      projectId: "your_project_id",
      storageBucket: "your_storage_bucket.appspot.com",
      // Add your messaging sender Id
      messagingSenderId: "000000000",
      // Add your App Id
      appId: "----------",
      // Add your measurementId
      measurementId: "G-21AWEQTWR",
    ),
  );