$ git clone -n https://src.fedoraproject.org/rpms/rubygem-backports.git /var/lib/mock/f39-build-1458048-33034/root/chroot_tmpdir/scmroot/rubygem-backports
Cloning into '/var/lib/mock/f39-build-1458048-33034/root/chroot_tmpdir/scmroot/rubygem-backports'...
$ git fetch origin e5396841f5437c1f94f72cf53f50f9eab905c96d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-backports
 * [new ref]         e5396841f5437c1f94f72cf53f50f9eab905c96d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e539684 Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild