submodule: bump third_party/openthread/repo from `5516024` to `cba1beb` (#1518)
submodule: bump third_party/openthread/repo from `5516024` to `cba1beb` (#1518)

Bumps [third_party/openthread/repo](https://github.com/openthread/openthread) from `5516024` to `cba1beb`.
- [Commits](https://github.com/openthread/openthread/compare/551602490555033a010ed4b4649821df4b2b882d...cba1bebf1f1ef3531bfe5397c75c3c6e045218b6)

---
updated-dependencies:
- dependency-name: third_party/openthread/repo
  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/borderrouter,openthread/ot-br-posix,openthread/borderrouter,openthread/ot-br-posix,openthread/borderrouter,openthread/ot-br-posix,openthread/borderrouter,openthread/ot-br-posix,openthread/borderrouter,openthread/ot-br-posix,openthread/borderrouter,openthread/ot-br-posix