$ git clone -n https://src.fedoraproject.org/rpms/libesmtp.git /var/lib/mock/f45-build-16126-483/root/chroot_tmpdir/scmroot/libesmtp
Cloning into '/var/lib/mock/f45-build-16126-483/root/chroot_tmpdir/scmroot/libesmtp'...
$ git fetch origin 594c4e53fdf466a596f42dd2535a11d2e03e25cf:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libesmtp
 * [new ref]         594c4e53fdf466a596f42dd2535a11d2e03e25cf -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 594c4e5 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild