Updated changelog

Author: mivano

CHANGES.md

@@ -5,6 +5,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+
+
+## [8.4.1] - 2020-09-28
 ### Fixed
 - Make sure TypeName is set to `_doc` when setting the template version to `ESv7`.
    The regression was introduced in `8.4.0`. #364