tree-wide: fix deprecated GitLab URLs

They will stop working in the next GitLab release, so let's update them
ASAP to make sure things are propagated to everyone by then.

See:
https://about.gitlab.com/releases/2020/05/06/gitlab-com-13-0-breaking-changes/#removal-of-deprecated-project-paths

Cc: mesa-stable@lists.freedesktop.org
Signed-off-by: Eric Engestrom <eric@engestrom.ch>
Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5111>
16 files changed