3.13.4 release notes: correct more typos

Author: michaelklishin

release-notes/3.13.4.md

@@ -122,9 +122,9 @@ Release notes can be found on GitHub at [rabbitmq-server/release-notes](https://
 
 ### OAuth 2 Plugin
 
-#### Enhancenements
+#### Enhancements
 
- * OpenID Connection endpoint now can be overridden for identity providers with
+ * OpenID Connect discovery endpoint now can be overridden for identity providers with
    non-standard configurations.
 
    GitHub issue: [#11103](https://github.com/rabbitmq/rabbitmq-server/issues/11103)