submodule: bump third_party/openthread/repo from 3560870 to `4e9d36…

…2` (#2645)

Bumps [third_party/openthread/repo](https://github.com/openthread/openthread) from `3560870` to `4e9d362`.
- [Commits](openthread/openthread@3560870...4e9d362)

---
updated-dependencies:
- dependency-name: third_party/openthread/repo
  dependency-type: direct:production
...

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