Prevent simultaneous deploys from different projects to the same environment
I have multiple projects which I would like to deploy to common environment. While making deploy I need to just copy a directory, and rebuild index file (just plaintext). When 2 projects will try to deploy at the same time, we may expect the first deploy's update of index will get overwritten by the second one. Is there any feature to lock deploy environments for the time of deploy? so CI would simply wait for other deploy to finish before doing own deploy to same environment.
This is a multi-project version of https://gitlab.com/gitlab-org/gitlab-ce/issues/20481, which provides locking semaphores per-project.