Upgrade Ruby to 2.5.3
See https://www.ruby-lang.org/en/news/2017/12/25/ruby-2-5-0-released/
- CE MR: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/22555
- EE MR: https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/8069
- Gitaly MR: gitaly!942 (merged)
Test pipeline where all builds succeeded: https://dev.gitlab.org/gitlab/omnibus-gitlab/pipelines/97424
Edited by GitLab Release Tools Bot