$ git clone -n https://src.fedoraproject.org/rpms/librepo.git /var/lib/mock/f41-build-side-1-3057350-38399/root/chroot_tmpdir/scmroot/librepo
Cloning into '/var/lib/mock/f41-build-side-1-3057350-38399/root/chroot_tmpdir/scmroot/librepo'...
$ git fetch origin 5af08dd2c58d14b875e5ae10efa7450a1d0a42c2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/librepo
 * [new ref]         5af08dd2c58d14b875e5ae10efa7450a1d0a42c2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5af08dd Update to 1.19.0