update docs

CHANGES.md

@@ -2,7 +2,16 @@
 
 ## v4.1.0-RC
 
-* 
+### BREAKING CHANGES
+
+* GROWI v4.1.x no longer support growi-plugin-attachment-refs@v1
+
+Upgrading Guide: <https://docs.growi.org/en/admin-guide/upgrading/41x.html>
+
+### Updates
+
+
+
 
 ## v4.0.10