refactor: renamed stories

packages/pinball_components/sandbox/lib/stories/flutter_forest/dash_bumper_a_game.dart

@@ -14,7 +14,7 @@ class DashBumperAGame extends BallGame {
         );
 
   static const description = '''
-    Shows how the "a: DashBumper is rendered.
+    Shows how the "a" DashBumper is rendered.
 
     - Activate the "trace" parameter to overlay the body.
 ''';

packages/pinball_components/sandbox/lib/stories/flutter_forest/stories.dart

@@ -13,17 +13,17 @@ void addFlutterForestStories(Dashbook dashbook) {
       gameBuilder: (_) => SignpostGame(),
     )
     ..addGame(
-      title: 'Big Dash Bumper',
+      title: 'Main Dash Bumper',
       description: DashBumperMainGame.description,
       gameBuilder: (_) => DashBumperMainGame(),
     )
     ..addGame(
-      title: 'Small Dash Bumper A',
+      title: 'Dash Bumper A',
       description: DashBumperAGame.description,
       gameBuilder: (_) => DashBumperAGame(),
     )
     ..addGame(
-      title: 'Small Dash Bumper B',
+      title: 'Dash Bumper B',
       description: DashBumperBGame.description,
       gameBuilder: (_) => DashBumperBGame(),
     );