Update changelog

Author: T4rk1n

CHANGELOG.md

@@ -7,6 +7,7 @@ This project adheres to [Semantic Versioning](https://semver.org/).
 ## Fixed
 
 - [#2987](https://github.com/plotly/dash/pull/2987) Fix multioutput requiring same number of no_update. Fixes [#2986](https://github.com/plotly/dash/issues/2986)
+- [2988](https://github.com/plotly/dash/pull/2988) Fix error handler and grouped outputs. Fixes [#2983](https://github.com/plotly/dash/issues/2983)
 
 ## Deprecated