refactor: fixed analyser warnings

lib/game/components/flutter_forest/cubit/flutter_forest_cubit.dart

@@ -4,9 +4,14 @@ import 'package:pinball_components/pinball_components.dart';
 
 part 'flutter_forest_state.dart';
 
+// TODO(alestiago): Evaluate if there is any useful documentation that could
+// be added to this class.
+// ignore: public_member_api_docs
 class FlutterForestCubit extends Cubit<FlutterForestState> {
-  FlutterForestCubit() : super(FlutterForestState.initial());
+  // ignore: public_member_api_docs
+  FlutterForestCubit() : super(const FlutterForestState.initial());
 
+  /// Event added when a bumper contacts with a ball.
   void onBumperActivated(DashNestBumper dashNestBumper) {
     emit(
       state.copyWith(
@@ -15,6 +20,7 @@ class FlutterForestCubit extends Cubit<FlutterForestState> {
     );
   }
 
+  /// Event added after the bonus is activated.
   void onBonusApplied() {
     emit(
       state.copyWith(activatedBumpers: const {}),

lib/game/pinball_game.dart

@@ -139,7 +139,7 @@ class DebugPinballGame extends PinballGame with FPSCounter, TapDetector {
   @override
   Future<void> onLoad() async {
     await super.onLoad();
-    // await _loadBackground();
+    await _loadBackground();
     await add(_DebugInformation());
   }
 

test/game/components/flutter_forest_test.dart

@@ -1,10 +1,7 @@
 // ignore_for_file: cascade_invocations
 
-import 'package:bloc_test/bloc_test.dart';
 import 'package:flame_test/flame_test.dart';
-import 'package:flutter/rendering.dart';
 import 'package:flutter_test/flutter_test.dart';
-import 'package:mocktail/mocktail.dart';
 import 'package:pinball/game/game.dart';
 import 'package:pinball_components/pinball_components.dart';