chore(CHANGELOG): update to v5.22.0

Author: philippfromme

CHANGELOG.md

@@ -6,6 +6,8 @@ All notable changes to [bpmn-js-properties-panel](https://github.com/bpmn-io/bpm
 
 ___Note:__ Yet to be released changes appear here._
 
+## 5.22.0
+
 * `FEAT`: add _Priority_ entry to user task _Assignment_ group ([#1072](https://github.com/bpmn-io/bpmn-js-properties-panel/pull/1072))
 
 ## 5.21.0