submodule: bump openthread from 289d137 to 9f30e04 (#234)

Bumps [openthread](https://github.com/openthread/openthread) from `289d137` to `9f30e04`.
- [Commits](openthread/openthread@289d137...9f30e04)

---
updated-dependencies:
- dependency-name: openthread
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

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