$ git clone -n https://src.fedoraproject.org/rpms/rust-uu_fold.git /var/lib/mock/f40-build-774049-127569/root/chroot_tmpdir/scmroot/rust-uu_fold
Cloning into '/var/lib/mock/f40-build-774049-127569/root/chroot_tmpdir/scmroot/rust-uu_fold'...
$ git fetch origin c54aacc2bce79e2e638855ca7af26a36be216416:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-uu_fold
 * [new ref]         c54aacc2bce79e2e638855ca7af26a36be216416 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c54aacc Initial package (rhbz#2258124)