Add v6.11.0 to CHANGELOG for ember-source

(cherry picked from commit 3482750)

Author: kategengler

CHANGELOG.md

@@ -1,11 +1,8 @@
 # Ember Changelog
 
-## v6.11.0-beta.2 (February 2, 2026)
+## v6.11.0 (February 17, 2026)
 
 - [#21024](https://github.com/emberjs/ember.js/pull/21024) [Bugfix] Add @ember/reactive into the AMD bundles
-
-## v6.11.0-beta.1 (January 6, 2026)
-
 - [#21014](https://github.com/emberjs/ember.js/pull/21014) Rename default export `GlimmerComponent` to `Component` for autocomplete DX
 
 ## v6.10.1 (February 2, 2026)