3.12.0 release notes edits

(cherry picked from commit 8593d1d)

Author: michaelklishin

release-notes/3.12.0.md

@@ -146,9 +146,15 @@ in the `3.11.x` release series.
 
    GitHub issue: [#7208](https://github.com/rabbitmq/rabbitmq-server/issues/7208).
 
- * Policies can now be defined to only apply to specific queue types. For example, you can have two policies that match all queue names ('.*')
-   but different queue types, so that different parameters are applied to all queues of a specific type. Example usage:
-   ```
+ * Policies can now be defined to only apply to specific queue types.
+
+   For example, it is now possible to have two policies matching all queue names ('.*')
+   but one applicable only to one queue type, and the other only to different queue type,
+   without conflicts.
+
+   For example, this policy will only apply to quorum queues and not streams or classic queues:
+
+   ``` bash
    rabbitmqctl set_policy at-least-once-dead-lettering ".*" '{"dead-letter-strategy": "at-least-once"}' --apply-to quorum_queues
    ```