Update Changelog

CHANGELOG.md

@@ -19,6 +19,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 ### Fixed
 
 - Fix depricatied action names in Reports, move actions that manage users from Reports to reports module
+- Allow using underscores and hyphens in new account's usernames
 
 
 ## [2.1] - 2020-08-26