fix(deps): update dependency firebase_core to v4

Author: renovate[bot]

pubspec.yaml

@@ -13,7 +13,7 @@ dependencies:
     sdk: flutter
 
   # Firebase
-  firebase_core: ^3.4.0
+  firebase_core: 4.5.0
   firebase_auth: ^5.2.0
   firebase_auth_platform_interface: ^7.0.0