make .gitlab-ci less pretty

.gitlab-ci.yml

@@ -10,9 +10,10 @@ image: "${CI_REGISTRY_IMAGE}/openappstack-ci:${CI_COMMIT_REF_NAME}"
 variables:
   SSH_KEY_ID: "411"
   HOSTNAME: "ci-$CI_PIPELINE_ID"
-  SUBDOMAIN: "$HOSTNAME.ci"
+  # Repeated values, because we're not allowed to use a variable in a variable
+  SUBDOMAIN: "ci-$CI_PIPELINE_ID.ci"
   DOMAIN: "openappstack.net"
-  ADDRESS: "$SUBDOMAIN.$DOMAIN"
+  ADDRESS: "ci-$CI_PIPELINE_ID.ci.openappstack.net"
 
 ci_test_image:
   stage: build