Fix Water duping with ice

FightSystem_Main/src/de/steamwar/fightsystem/listener/InFightInventoryListener.java

@@ -99,6 +99,9 @@ public class InFightInventoryListener extends BasicListener {
             case PISTON_HEAD:
                 type = Material.PISTON;
                 break;
+            case ICE:
+            case PACKED_ICE:
+                return;
         }
         ItemStack itemStack;