submodule: bump openthread from `62ae1a1` to `3e833c1` (#18)
submodule: bump openthread from `62ae1a1` to `3e833c1` (#18)

Bumps [openthread](https://github.com/openthread/openthread) from `62ae1a1` to `3e833c1`.
- [Commits](https://github.com/openthread/openthread/compare/62ae1a1c364d2a35f0c6d9f10e485d03751053d6...3e833c120ff9dda92af315406266c453d2ac3699)

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

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