Fix T98316: geometry nodes stop updating after duplication

This was a missing depsgraph update.

source/blender/editors/object/object_modifier.cc

@@ -3399,6 +3399,7 @@ static int geometry_node_tree_copy_assign_exec(bContext *C, wmOperator *UNUSED(o
   nmd->node_group = new_tree;
   id_us_min(&tree->id);
 
+  DEG_relations_tag_update(bmain);
   WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
   return OPERATOR_FINISHED;
 }