submodule: bump third_party/openthread/repo from `38418ae` to `65bc830` (#2240)

Bumps [third_party/openthread/repo](https://github.com/openthread/openthread) from `38418ae` to `65bc830`.
- [Commits](https://github.com/openthread/openthread/compare/38418aebe467a12102685af850a15686182aaa81...65bc830edb26f6a2ba2509f8a490f8bd20b8bddb)

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

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
diff --git a/third_party/openthread/repo b/third_party/openthread/repo
index 38418ae..65bc830 160000
--- a/third_party/openthread/repo
+++ b/third_party/openthread/repo
@@ -1 +1 @@
-Subproject commit 38418aebe467a12102685af850a15686182aaa81
+Subproject commit 65bc830edb26f6a2ba2509f8a490f8bd20b8bddb