Use MR URL instead of IID in release check command
Allow the release check command to take an MR URL as argument instead of MR IID. So the command would be release check https://gitlab.com/gitlab-org/gitlab/-/merge_requests/12345 instead of release check 12345.
This should make it easier for developers to use the command, and will also allow for MRs from the security and gitlab-foss project.
Edited by Reuben Pereira