Release v6.6.0

Author: siirimangus

CHANGELOG.md

@@ -5,8 +5,11 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+
+## [6.6.0](https://github.com/pipedrive/client-php/compare/6.5.1...6.6.0) (2024-04-02)
+
 ### Added
-- Added documentation for new endpoint `/deals/{id}/participantsChangelog`.
+- Documentation for new endpoint `/deals/{id}/participantsChangelog`
 
 ## [6.5.1](https://github.com/pipedrive/client-php/compare/6.5.0...6.5.1) (2024-04-02)