r/minio-backups-cert: Enable/start cerbot timer

Forgot to ensure the _certbot-renew.timer_ unit was enabled and started,
so the MinIO certificate did not get renewed the first time.

roles/minio-backups-cert/tasks/main.yml

@@ -77,4 +77,15 @@
   - restart certbot-renew timer
   tags:
   - systemd
-
+- name: ensure certbot-renew timer unit is enabled
+  systemd:
+    name: certbot-renew.timer
+    enabled: true
+  tags:
+  - service
+- name: ensure certbot-renew timer is running
+  systemd:
+    name: certbot-renew.timer
+    state: started
+  tags:
+  - service