Fix changelog

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

CHANGELOG

@@ -4,10 +4,9 @@ v 8.5.0 (unreleased)
   - Add "visibility" flag to GET /projects api endpoint
   - Upgrade gitlab_git to 7.2.23 to fix commit message mentions in first branch push
   - New UI for pagination
+  - Fix diff comments loaded by AJAX to load comment with diff in discussion tab
 
 v 8.4.0
-v 8.4.0 (unreleased)
-  - Fix diff comments loaded by AJAX to load comment with diff in discussion tab
   - Allow LDAP users to change their email if it was not set by the LDAP server
   - Ensure Gravatar host looks like an actual host
   - Consider re-assign as a mention from a notification point of view