Bump third_party/ot-br-posix/repo from 13d583e to 9326cc3 (#31914)

Bumps [third_party/ot-br-posix/repo](https://github.com/openthread/ot-br-posix) from `13d583e` to `9326cc3`.
- [Release notes](https://github.com/openthread/ot-br-posix/releases)
- [Commits](openthread/ot-br-posix@13d583e...9326cc3)

---
updated-dependencies:
- dependency-name: third_party/ot-br-posix/repo
  dependency-type: direct:production
...

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