Bump third_party/openthread/repo from bc54d67 to 0019f38 (#37793)

Bumps [third_party/openthread/repo](https://github.com/openthread/openthread) from `bc54d67` to `0019f38`.
- [Release notes](https://github.com/openthread/openthread/releases)
- [Commits](openthread/openthread@bc54d67...0019f38)

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

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Author: dependabot[bot]