$ git clone -n https://src.fedoraproject.org/rpms/zimg.git /var/lib/mock/f42-build-3421858-45166/root/chroot_tmpdir/scmroot/zimg
Cloning into '/var/lib/mock/f42-build-3421858-45166/root/chroot_tmpdir/scmroot/zimg'...
$ git fetch origin 7f4b06d7deeb8d8450ce4bb5da7b53734b8b1df7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/zimg
 * [new ref]         7f4b06d7deeb8d8450ce4bb5da7b53734b8b1df7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7f4b06d Rebuilt for https://fedoraproject.org/wiki/Fedora_42_Mass_Rebuild