Add matrix_conduit_hostname

roles/custom/matrix-conduit/tasks/validate_config.yml

@@ -6,4 +6,5 @@
       You need to define a required configuration setting (`{{ item.name }}`).
   when: "item.when | bool and vars[item.name] == ''"
   with_items:
+    - {'name': 'matrix_conduit_hostname', when: true}
     - {'name': 'matrix_conduit_container_network', when: true}