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](https://github.com/openthread/ot-br-posix/compare/13d583e361c7038b967b601d5e5f6739b0bcf736...9326cc38b6b6ce81958a96d7821c4cb21976d636)

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

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
diff --git a/third_party/ot-br-posix/repo b/third_party/ot-br-posix/repo
index 13d583e..9326cc3 160000
--- a/third_party/ot-br-posix/repo
+++ b/third_party/ot-br-posix/repo
@@ -1 +1 @@
-Subproject commit 13d583e361c7038b967b601d5e5f6739b0bcf736
+Subproject commit 9326cc38b6b6ce81958a96d7821c4cb21976d636