Add shutdown of bau after one minute no player

BauSystem_Main/src/de/steamwar/bausystem/BauSystem.java

@@ -165,7 +165,7 @@ public class BauSystem extends JavaPlugin implements Listener {
         Player p = e.getPlayer();
         SWScoreboard.removeScoreboard(p);
         if (Bukkit.getOnlinePlayers().isEmpty() || (Bukkit.getOnlinePlayers().size() == 1 && Bukkit.getOnlinePlayers().contains(p))) {
-            Bukkit.shutdown();
+            autoShutdown = Bukkit.getScheduler().runTaskLater(this, Bukkit::shutdown, 1200);
         }
     }