Reapply " [config_drive]fix _user_data_change fails assertion"

This reverts commit 052ccea.

Author: hjensas

roles/config_drive/tasks/main.yml

@@ -84,7 +84,7 @@
   ansible.builtin.assert:
     that:
       - _meta_data_change is not changed
-      - _user_data_change is not changed
+      - _user_data_change is skipped or _user_data_change is not changed
       - _net_data_change is not changed
     msg: >-
       You're trying to edit an existing ISO. This isn't possible,