$ git clone -n https://src.fedoraproject.org/rpms/vacation.git /var/lib/mock/f45-build-37862-718/root/chroot_tmpdir/scmroot/vacation
Cloning into '/var/lib/mock/f45-build-37862-718/root/chroot_tmpdir/scmroot/vacation'...
$ git fetch origin 7e645e78fcba392f336d5fb92d5682b74324257f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/vacation
 * [new ref]         7e645e78fcba392f336d5fb92d5682b74324257f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7e645e7 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild