and `pub_key_bytes` in `privval.PubKeyResponse`, `types.Validator` and
`types.SimpleValidator`.

Closes #2878
Follow-up to #2843
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---

#### PR checklist

- [x] Tests written/updated
- [x] Changelog entry added in `.changelog` (we use
[unclog](https://github.com/informalsystems/unclog) to manage our
changelog)
- [ ] Updated relevant documentation (`docs/` or `spec/`) and code
comments
- [x] Title follows the [Conventional
Commits](https://www.conventionalcommits.org/en/v1.0.0/) spec

---------

Co-authored-by: Sergio Mena <sergio@informal.systems>
(cherry picked from commit d342b3a)