$ git clone -n https://src.fedoraproject.org/rpms/rubygem-rb-readline.git /var/lib/mock/f45-build-35272-694/root/chroot_tmpdir/scmroot/rubygem-rb-readline
Cloning into '/var/lib/mock/f45-build-35272-694/root/chroot_tmpdir/scmroot/rubygem-rb-readline'...
$ git fetch origin 38b26d6a8d7585fd704fbb1f5eb05129c1bad440:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-rb-readline
 * [new ref]         38b26d6a8d7585fd704fbb1f5eb05129c1bad440 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 38b26d6 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild