Convert GitLab diffs back to patches

GitLab has fixed unstable footer, so restore header/footer.
https://gitlab.com/gitlab-org/gitaly/-/commit/8a1daafa720b

This reverts commit c031fd115a267199aa9cd9ee7d4a790ac6d27c03.

(cherry picked from commit fe9883e07c675cbf74a89481b560e6b5d845654a)