Update 3.13.7.md

(cherry picked from commit fb2d6f9)

Author: michaelklishin

release-notes/3.13.7.md

@@ -40,7 +40,7 @@ Release notes can be found on GitHub at [rabbitmq-server/release-notes](https://
 
    GitHub issue: [#12073](https://github.com/rabbitmq/rabbitmq-server/pull/12073)
 
- * Classic [peer discovery](https://www.rabbitmq.com/docs/cluster-formation) now logs warnings for certain common user mistakes.
+ * Config file [peer discovery](https://www.rabbitmq.com/docs/cluster-formation) now logs warnings for certain common user mistakes.
 
    GitHub issues: [#11586](https://github.com/rabbitmq/rabbitmq-server/issues/11586), [#11898](https://github.com/rabbitmq/rabbitmq-server/pull/11898)