Fix certbot -d argument for new certificates

trim_blocks removed the newline after {% endif %}, so the command became '-d example.org-m mail@...' and certbot refused it. Only hit for domains without an existing certificate.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tasks/letsencrypt.yml

@@ -33,7 +33,7 @@
     cmd: |
       certbot
       --nginx
-      -d {% if cert_domain is not string and cert_domain is iterable %}{{ cert_domain | join(',') }}{% else %}{{ cert_domain }}{% endif %}
+      -d {{ cert_domain | join(',') if (cert_domain is not string and cert_domain is iterable) else cert_domain }}
       -m {{ letsencrypt_mail_address }}
       --agree-tos
       --noninteractive