sexp: init at 0.8.6 (#240252)
This is a dependency of the [next version](https://github.com/rnpgp/rnp/releases/tag/v0.17.0)
of [rnp](https://github.com/NixOS/nixpkgs/blob/a04b45f10eddb02352574d95c7d0a76bfbfc11dc/pkgs/tools/security/rnp/default.nix#L17).
(cherry picked from commit d8c6a48180ef9ad587149eac65e554cf773b302b)
Co-authored-by: Jeffrey Lau <jeffrey.lau@ribose.com>
![github-actions[bot]](https://avatars.githubusercontent.com/in/15368?v=4&s=60)