docker_service: let the dry run of a new service pass

In check mode nothing is written, so for a service that is not on the
host yet the restart task finds no project directory and fails the
whole dry run. Ignore errors there in check mode, as the compose task
already does.

Assisted-by: Claude:opus-5-5

ansible/roles/docker_service/tasks/main.yaml

@@ -111,6 +111,8 @@
     - service_restart_on_change
     - template_result is changed or file_result is changed
     - compose_result is not changed
+  # A first dry run has no project directory to restart yet
+  ignore_errors: "{{ ansible_check_mode }}"
 
 - name: Wait before health check
   ansible.builtin.pause: