Update dependency firebase_core to v3

Author: renovate[bot]

pubspec.yaml

@@ -9,7 +9,7 @@ environment:
 
 dependencies:
   # firebase
-  firebase_core: ^2.15.0
+  firebase_core: ^3.0.0
   firebase_core_platform_interface: ^5.0.0
   firebase_crashlytics: ^3.3.4
   firebase_messaging: ^14.6.5