$ git clone -n https://src.fedoraproject.org/rpms/python-siphash.git /var/lib/mock/f45-build-32974-665/root/chroot_tmpdir/scmroot/python-siphash
Cloning into '/var/lib/mock/f45-build-32974-665/root/chroot_tmpdir/scmroot/python-siphash'...
$ git fetch origin 601edff715d010b88a4797ef6dbcb89befad13e3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/python-siphash
 * [new ref]         601edff715d010b88a4797ef6dbcb89befad13e3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 601edff Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild