submodule: bump third_party/openthread/repo from `53af491` to `5f39ba0` (#934)
submodule: bump third_party/openthread/repo from `53af491` to `5f39ba0` (#934)

Bumps [third_party/openthread/repo](https://github.com/openthread/openthread) from `53af491` to `5f39ba0`.
- [Commits](https://github.com/openthread/openthread/compare/53af491df5c45a60a01e1ff9522e6110ec7808c0...5f39ba055bb5adcc28fd545226cbd6836a015c2e)

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

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

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