$ git clone -n https://src.fedoraproject.org/rpms/rust-nu-protocol.git /var/lib/mock/f40-build-2723428-73099/root/chroot_tmpdir/scmroot/rust-nu-protocol
Cloning into '/var/lib/mock/f40-build-2723428-73099/root/chroot_tmpdir/scmroot/rust-nu-protocol'...
$ git fetch origin 63597e16cabe583ea13d86e65e1a18d78e18de52:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-nu-protocol
 * [new ref]         63597e16cabe583ea13d86e65e1a18d78e18de52 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 63597e1 Update to 0.91.0 (rhbz#2257511)