Finish Action Cable section in release notes

[ci skip]

guides/source/5_1_release_notes.md

@@ -252,6 +252,12 @@ Please refer to the [Changelog][action-cable] for detailed changes.
     with multiple applications.
     ([Pull Request](https://github.com/rails/rails/pull/27425))
 
+*   Permit same-origin connections by default.
+    ([commit](https://github.com/rails/rails/commit/dae404473409fcab0e07976aec626df670e52282))
+
+*   Add `ActiveSupport::Notifications` hook for broadcasing data.
+    ([Pull Request](https://github.com/rails/rails/pull/24988))
+
 Action Pack
 -----------