Add run_if to score manager system

src/bin/flappy/main.rs

@@ -85,8 +85,7 @@ fn main() {
                 update_tooltip.run_if(in_state(DebuggingState::On)),
                 // TODO: Add run_if to this system
                 hitbox_collision_handler,
-                // TODO: Add run_if to this system
+                manage_score.run_if(on_event::<CollisionStarted>.or(on_event::<CollisionEnded>)),
-                manage_score,
             ),
         )
         .add_observer(flap)