submodule: bump third_party/openthread/repo from 6831210 to `c58355…

…4` (#2722)

Bumps [third_party/openthread/repo](https://github.com/openthread/openthread) from `6831210` to `c583554`.
- [Commits](openthread/openthread@6831210...c583554)

---
updated-dependencies:
- dependency-name: third_party/openthread/repo
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>