Update 4.0.4 release notes

(cherry picked from commit 37f7b3f)

Author: michaelklishin

release-notes/4.0.4.md

@@ -52,6 +52,11 @@ Release notes can be found on GitHub at [rabbitmq-server/release-notes](https://
 
    GitHub issue: [#12700](https://github.com/rabbitmq/rabbitmq-server/pull/12700)
 
+ * Nodes using Khepri for schema data store now follow a set of `rabbitmqctl reset` procedures
+   better aligned with those performed by nodes still using Mnesia.
+
+   GitHub issue: [#12763](https://github.com/rabbitmq/rabbitmq-server/pull/12763)
+
 #### Enhancements
 
  * Policy changes are now periodicaly re-applied (only if necessary) to quorum queues.