Move Changelog entry for note validation to 8.9

CHANGELOG

@@ -2,6 +2,7 @@ Please view this file on the master branch, on stable branches it's out of date.
 
 v 8.9.0 (unreleased)
   - Allow forking projects with restricted visibility level
+  - Improve note validation to prevent errors when creating invalid note via API
   - Redesign navigation for project pages
   - Fix groups API to list only user's accessible projects
   - Redesign account and email confirmation emails
@@ -63,7 +64,6 @@ v 8.8.0
   - Make 'upcoming' filter for milestones work better across projects
   - Sanitize repo paths in new project error message
   - Bump mail_room to 0.7.0 to fix stuck IDLE connections
-  - Improve note validation to prevent errors when creating invalid note via API
   - Remove future dates from contribution calendar graph.
   - Support e-mail notifications for comments on project snippets
   - Fix API leak of notes of unauthorized issues, snippets and merge requests