Bump version in changelog

Author: grst

CHANGELOG.md

@@ -8,7 +8,7 @@ and this project adheres to [Semantic Versioning][].
 [keep a changelog]: https://keepachangelog.com/en/1.0.0/
 [semantic versioning]: https://semver.org/spec/v2.0.0.html
 
-## Unreleased
+## v0.22.0
 
 ### Fixes