add an item to changelog

Author: UUGTech

CHANGELOG.md

@@ -7,6 +7,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+### Added
+* add sort_by popup to branchlist [[@UUGTech](https://github.com/UUGTech)]([#2146](https://github.com/extrawurst/gitui/issues/2146))
+
 ### Fixes
 * blame sometimes crashed due to new syntax highlighting [[@tdtrung17693](https://github.com/tdtrung17693)] ([#2130](https://github.com/extrawurst/gitui/issues/2130))