refactor: load dino walls assets from cache

packages/pinball_components/lib/src/components/dino_walls.dart

@@ -106,8 +106,10 @@ class _DinoTopWallSpriteComponent extends SpriteComponent with HasGameRef {
   @override
   Future<void> onLoad() async {
     await super.onLoad();
-    final sprite = await gameRef.loadSprite(
+    final sprite = Sprite(
+      gameRef.images.fromCache(
         Assets.images.dino.dinoLandTop.keyName,
+      ),
     );
     this.sprite = sprite;
     size = sprite.originalSize / 10;
@@ -212,8 +214,10 @@ class _DinoBottomWallSpriteComponent extends SpriteComponent with HasGameRef {
   @override
   Future<void> onLoad() async {
     await super.onLoad();
-    final sprite = await gameRef.loadSprite(
+    final sprite = Sprite(
+      gameRef.images.fromCache(
         Assets.images.dino.dinoLandBottom.keyName,
+      ),
     );
     this.sprite = sprite;
     size = sprite.originalSize / 10;

test/game/pinball_game_test.dart

@@ -52,6 +52,8 @@ void main() {
     Assets.images.boundary.bottom.keyName,
     Assets.images.slingshot.upper.keyName,
     Assets.images.slingshot.lower.keyName,
+    Assets.images.dino.dinoLandTop.keyName,
+    Assets.images.dino.dinoLandBottom.keyName,
   ];
   final flameTester = FlameTester(() => PinballTestGame(assets));
   final debugModeFlameTester = FlameTester(() => DebugPinballTestGame(assets));