submodule: bump openthread from `812c36f` to `4a0d069` (#421)
submodule: bump openthread from `812c36f` to `4a0d069` (#421)

Bumps [openthread](https://github.com/openthread/openthread) from `812c36f` to `4a0d069`.
- [Commits](https://github.com/openthread/openthread/compare/812c36f6581967b3d9af8361f00716c75f47473c...4a0d069ee81aa530c8d0641f37d3561e53e26d5f)

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

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>
Co-authored-by: dependabot[bot] <1c358da00a777d4e9898c1280ab801e2df165188@users.noreply.github.com>
openthread/ot-efr32,openthread/ot-efr32,openthread/ot-efr32