Fix some disc selectors not working

src/main/java/emu/nebula/game/inventory/Inventory.java

@@ -679,9 +679,7 @@ public class Inventory extends PlayerManager implements GameDatabaseObject {
         }
 
         // Sanity check
-        if (count <= 0) {
-            return change;
-        }
+        count = Math.max(count, 1);
         
         // Get item data
         var data = GameData.getItemDataTable().get(id);