fix: add back lua.gc_stop()

There seems to be a (more severe) deadlock again, due to commit
b55207a559. Need to investigate further.

This is possibly because of azalea's ContainerRef::close(), which
locks some mutex.

src/events.rs

@@ -14,6 +14,8 @@ use tokio::net::TcpListener;
 
 #[allow(clippy::too_many_lines)]
 pub async fn handle_event(client: Client, event: Event, state: State) -> anyhow::Result<()> {
+    state.lua.gc_stop();
+
     match event {
         Event::AddPlayer(player_info) => {
             call_listeners(&state, "add_player", Player::from(player_info)).await;