npc buildings dont accumulate gold

src/engine/objects/Building.java

@@ -1000,7 +1000,10 @@ public class Building extends AbstractWorldObject {
     public final boolean setStrongboxValue(int newValue) {
 
         boolean success = true;
-
+        if(this.isOwnerIsNPC()) {
+            newValue = 0;
+            this.setStrongboxValue(0);
+        }
         try {
             DbManager.BuildingQueries.SET_PROPERTY(this, "currentGold", newValue);
             this._strongboxValue = newValue;