Merge branch 'fail-danger-in-ci' into 'master'

Don't allow Danger to fail in CI any more

Closes gitlab-org/release/framework#21

See merge request gitlab-org/gitlab-ce!23695

.gitlab-ci.yml

@@ -488,7 +488,6 @@ danger-review:
   <<: *pull-cache
   image: registry.gitlab.com/gitlab-org/gitlab-build-images:danger
   stage: test
-  allow_failure: true
   dependencies: []
   before_script: []
   only: