fix YAML even more

.gitlab-ci.yml

@@ -34,7 +34,7 @@ opam:
   # Send a trigger to the repository doing the work
   - curl --fail -X POST -F "token=$OPAM_UPDATE_SECRET" -F "ref=master" -F "variables[REPO]=${CI_PROJECT_URL}.git" -F "variables[REF]=$CI_COMMIT_REF_NAME" -F "variables[SHA]=$CI_COMMIT_SHA" -F "variables[NAME]=$OPAM_PKG" https://gitlab.mpi-sws.org/api/v3/projects/581/trigger/builds
   variables:
-  - OPAM_PKG: "coq-iris"
+    OPAM_PKG: "coq-iris"
   only:
   - master