Handle blob removal in spawn system

src/main.js

@@ -529,7 +529,7 @@
               clearedByColor[key] = (clearedByColor[key] || 0) + 1;
             }
           });
-        removeBlob(id);
+        spawnSystem.removeBlob(id);
       });
       // Remove cleared balls from tracking list.
       for (let i = balls.length - 1; i >= 0; i -= 1) {