fix(schematic_selector): Fix Player Head in 1.12

Signed-off-by: Chaos <chaoscaot444@gmail.com>

SpigotCore_Main/src/de/steamwar/inventory/SchematicSelector.java

@@ -293,7 +293,7 @@ public class SchematicSelector {
                 openFilter();
             } else {
                 SWAnvilInv swAnvilInv = new SWAnvilInv(player, Core.MESSAGE.parse("SCHEM_SELECTOR_FILTER_ENTER_OWNER", player));
-                swAnvilInv.setItem(Material.PLAYER_HEAD);
+                swAnvilInv.setItem(SWItem.getMaterial("SKULL_ITEM"), (byte) 3);
                 swAnvilInv.setCallback(s -> {
                     if(SteamwarUser.get(s) != null) {
                         filter.setOwner(SteamwarUser.get(s).getId());