submodule: bump openthread from 193e77e to 22fcb0e (#610)

Bumps [openthread](https://github.com/openthread/openthread) from `193e77e` to `22fcb0e`.
- [Commits](openthread/openthread@193e77e...22fcb0e)

---
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>