www/gitlab: security and patch update to 18.11.3
Changes: https://docs.gitlab.com/releases/patches/patch-release-gitlab-18-11-3-released/
Security: b3cb8f40-4f4c-11f1-80f1-2cf05da270f3
(cherry picked from commit 8e22b32de7529c07546882b1cca31ae00c5d57da)