$ git clone -n https://src.fedoraproject.org/rpms/python-grokmirror.git /var/lib/mock/f45-build-30896-648/root/chroot_tmpdir/scmroot/python-grokmirror
Cloning into '/var/lib/mock/f45-build-30896-648/root/chroot_tmpdir/scmroot/python-grokmirror'...
$ git fetch origin 4d56572c311920a05671a216f8b3435aa6f0ebfa:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/python-grokmirror
 * [new ref]         4d56572c311920a05671a216f8b3435aa6f0ebfa -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4d56572 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild