$ git clone -n https://src.fedoraproject.org/rpms/dnf-plugin-cow.git /var/lib/mock/f40-build-2661935-66927/root/chroot_tmpdir/scmroot/dnf-plugin-cow
Cloning into '/var/lib/mock/f40-build-2661935-66927/root/chroot_tmpdir/scmroot/dnf-plugin-cow'...
$ git fetch origin cab13a8d2501454713504a7f8b7c149356d1d28c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/dnf-plugin-cow
 * [new ref]         cab13a8d2501454713504a7f8b7c149356d1d28c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at cab13a8 Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild