Update 3.12.5 release notes

Author: michaelklishin

release-notes/3.12.5.md

@@ -27,7 +27,7 @@ Release notes can be found on GitHub at [rabbitmq-server/release-notes](https://
 
 #### Bug Fixes
 
- * Quorum queue leader is now correctly observed in certain network failure scenarios.
+ * Quorum queue leader changes are now correctly observed in certain network failure scenarios.
 
    GitHub issues: [#9241](https://github.com/rabbitmq/rabbitmq-server/pull/9241), [#9227](https://github.com/rabbitmq/rabbitmq-server/pull/9227)