Add a prevention from NPE

src/main/java/com/Acrobot/ChestShop/Listeners/Player/PlayerTeleport.java

@@ -14,6 +14,10 @@ public class PlayerTeleport implements Listener {
 
     @EventHandler
     public static void onPlayerTeleport(PlayerTeleportEvent event) {
+        if (event.getPlayer() == null || event.getPlayer().getOpenInventory() == null) {
+            return;
+        }
+
         if (event.getPlayer().getOpenInventory().getType() != InventoryType.CRAFTING) {
             event.getPlayer().closeInventory();
         }