fix wrong version in changelog

Author: willmcgugan

CHANGELOG.md

@@ -5,7 +5,7 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
-## [2.5.6] - 2019-06-08
+## [2.4.6] - 2019-06-08
 
 ### Added