MFH: r522891 r522992

Bugfix update to 12.6.3.
Changelog:
https://about.gitlab.com/releases/2020/01/09/gitlab-12-6-3-released/

Security related update to 12.6.4.
Changelog:
https://about.gitlab.com/releases/2020/01/13/critical-security-release-gitlab-12-dot-6-dot-4-released/

Security: f929b172-369e-11ea-9cdb-001b217b3468

Approved by: ports-secteam (joneum)