$ git clone -n https://src.fedoraproject.org/rpms/perl-Math-Cartesian-Product.git /var/lib/mock/f45-build-24674-605/root/chroot_tmpdir/scmroot/perl-Math-Cartesian-Product
Cloning into '/var/lib/mock/f45-build-24674-605/root/chroot_tmpdir/scmroot/perl-Math-Cartesian-Product'...
$ git fetch origin 5e95742372541e27394b1f5033972557232532b9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Math-Cartesian-Product
 * [new ref]         5e95742372541e27394b1f5033972557232532b9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5e95742 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild