Maybe unstuck CI: Try 3

.gitlab-ci.yml

@@ -4,7 +4,8 @@ stages:
 .build:
   stage: build
   image: coqorg/${CI_JOB_NAME}
-  tags: au
+  tags:
+    - au
   before_script:
     - if [ -n "${COMPILER_EDGE}" ]; then opam switch ${COMPILER_EDGE} && eval $(opam env); fi
     - opam update -y