Bump third_party/openthread/repo from 287dbfa to e5aaa57

Bumps [third_party/openthread/repo](https://github.com/openthread/openthread) from `287dbfa` to `e5aaa57`.
- [Release notes](https://github.com/openthread/openthread/releases)
- [Commits](openthread/openthread@287dbfa...e5aaa57)

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

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