Use fully-qualified module names for builtin Ansible modules

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/1939

roles/matrix-etherpad/tasks/validate_config.yml

@@ -1,13 +1,13 @@
 ---
 
 - name: Fail if Etherpad is enabled without the Dimension integrations manager
-  fail:
+  ansible.builtin.fail:
     msg: >-
       To integrate Etherpad notes with Matrix rooms you need to set "matrix_dimension_enabled" to true
   when: "not matrix_dimension_enabled|bool"
 
 - name: Fail if no database is configured for Etherpad
-  fail:
+  ansible.builtin.fail:
     msg: >-
       Etherpad requires a dedicated Postgres database. Please enable the built in one, or configure an external DB by redefining "matrix_etherpad_database_hostname"
   when: matrix_etherpad_database_hostname == "matrix-postgres" and not matrix_postgres_enabled