$ git clone -n https://src.fedoraproject.org/rpms/rust-nu-system.git /var/lib/mock/f40-build-2073372-49358/root/chroot_tmpdir/scmroot/rust-nu-system
Cloning into '/var/lib/mock/f40-build-2073372-49358/root/chroot_tmpdir/scmroot/rust-nu-system'...
$ git fetch origin 1fddd4d9604e1f76d9ce1ebae6587a98405c6bf3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-nu-system
 * [new ref]         1fddd4d9604e1f76d9ce1ebae6587a98405c6bf3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1fddd4d Update to 0.86.0