Gitolite is now updated to version 3.6.14 in Guix:
https://codeberg.org/guix/guix/commit/690680eec7b1ffdefa493069f87a1e3ed37271d1
This version makes it possible to use any default branch name for the gitolite-admin repo, not just master. This also means that setting the default-branch field of the gitolite-git-configuration record (to anything other than #f or master) will now result in a working gitolite installation.