$ git clone -n https://src.fedoraproject.org/rpms/ruby.git /var/lib/mock/f39-build-2161177-50951/root/chroot_tmpdir/scmroot/ruby
Cloning into '/var/lib/mock/f39-build-2161177-50951/root/chroot_tmpdir/scmroot/ruby'...
$ git fetch origin 64dc6dd3e46e84ea84a142663753fa4b4a7dc29f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ruby
 * [new ref]         64dc6dd3e46e84ea84a142663753fa4b4a7dc29f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 64dc6dd Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild