Add GitLab branding links to each page
Because there is no "GitLab mandatory branding link" at the bottom of each page, users will never find the correct place to submit issues like https://gitlab.gnome.org/GNOME/gimp/-/issues/5849 .
Because there is no "GitLab mandatory branding link" at the bottom of each page, users will never find the correct place to submit issues like https://gitlab.gnome.org/GNOME/gimp/-/issues/5849 .