`game_template`: Revert analysis for `flutter_lints` (#1971)

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game_template/analysis_options.yaml

@@ -1,4 +1,4 @@
-include: package:analysis_defaults/flutter.yaml
+include: package:flutter_lints/flutter.yaml
 
 linter:
   rules:

game_template/pubspec.yaml

@@ -30,8 +30,7 @@ dependencies:
   in_app_purchase: ^3.0.1  # In-app purchases
 
 dev_dependencies:
-  analysis_defaults:
-    path: ../analysis_defaults
+  flutter_lints: ^2.0.2
   flutter_test:
     sdk: flutter
   flutter_launcher_icons: ^0.13.0