Fix wrong thread used after reloading world (#11704)

* Fix wrong thread used after reloading world

* Sync callback if possible

---------

Co-authored-by: someaddons <38401808+someaddons@users.noreply.github.com>

Author: uecasm

src/main/java/com/minecolonies/core/colony/workorders/AbstractWorkOrder.java

@@ -421,7 +421,14 @@ public String getStructurePack()
     @Override
     public void loadBlueprint(final Level world, final Consumer<Blueprint> afterLoad)
     {
-        loadBlueprintFuture(world).thenAccept(afterLoad);
+        if (blueprint != null)
+        {
+            afterLoad.accept(blueprint);
+        }
+        else
+        {
+            loadBlueprintFuture(world).thenAcceptAsync(afterLoad, WorldUtil.getMainThread(world));
+        }
     }
 
     @Override