roles/archweb: Fix typo on the custom nginx maintenance template

roles/archweb/templates/maintenance-nginx.d.conf.j2

@@ -158,7 +158,7 @@ server {
             access_log   /var/log/nginx/{{ archweb_domain }}/access.log main;
             uwsgi_pass archweb;
         }
-            
+
         return 503;
     }