message: update changelog for v18.0.0
diff: @@ -4,7 +4,7 @@ All notable changes to the project will be documented in this file.
  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]
  +## [18.0.0]
  ### Added
  