Move /projects/visible entry to 8.13

CHANGELOG

@@ -3,6 +3,7 @@ Please view this file on the master branch, on stable branches it's out of date.
 v 8.13.0 (unreleased)
   - Add link from system note to compare with previous version
   - Use gitlab-shell v3.6.2 (GIT TRACE logging)
+  - Add `/projects/visible` API endpoint (Ben Boeckel)
   - Fix centering of custom header logos (Ashley Dumaine)
   - AbstractReferenceFilter caches project_refs on RequestStore when active
   - Replaced the check sign to arrow in the show build view. !6501
@@ -155,7 +156,6 @@ v 8.12.0
   - Test migration paths from 8.5 until current release !4874
   - Replace animateEmoji timeout with eventListener (ClemMakesApps)
   - Show badges in Milestone tabs. !5946 (Dan Rowden)
-  - Add `/projects/visible` API endpoint (Ben Boeckel)
   - Optimistic locking for Issues and Merge Requests (title and description overriding prevention)
   - Require confirmation when not logged in for unsubscribe links !6223 (Maximiliano Perez Coto)
   - Add `wiki_page_events` to project hook APIs (Ben Boeckel)