submodule: bump openthread from `9021935` to `b34f2a3` (#232)
submodule: bump openthread from `9021935` to `b34f2a3` (#232)

Bumps [openthread](https://github.com/openthread/openthread) from `9021935` to `b34f2a3`.
- [Commits](https://github.com/openthread/openthread/compare/9021935bcc7b3b173524c8ddb627878614825e3e...b34f2a3fd378e703ce37e4c939940b49dcc56696)

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

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

Co-authored-by: dependabot[bot] <1c358da00a777d4e9898c1280ab801e2df165188@users.noreply.github.com>
openthread/ot-samr21,openthread/ot-samr21