📚doc: Update CHANGELOG

Author: negokaz

CHANGELOG.md

@@ -13,6 +13,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   This change will show you deserialization warnings during the rolling update, it's safe to ignore. 
   For more details, see [Akka 2.6.16 release note](https://akka.io/blog/news/2021/08/19/akka-2.6.16-released#rolling-upgrades)
 
+### Fixed
+- TestKit throws "Shard received unexpected message" exception after the entity passivated [PR#100](https://github.com/lerna-stack/akka-entity-replication/pull/100)
+
 ## [v2.0.0] - 2021-07-16
 [v2.0.0]: https://github.com/lerna-stack/akka-entity-replication/compare/v1.0.0...v2.0.0