Update changelog

Author: kinow

CHANGES.md

@@ -1,6 +1,6 @@
 # Active Choices plug-in changelog
 
-## Version 2.6.4 (2022/??/??)
+## Version 2.6.4 (2022/08/30)
 
 1. [JENKINS-69448](https://issues.jenkins.io/browse/JENKINS-69448): Groovy script returning a Map is not handled properly with timer, thanks to @ericcitaire
 2. [JENKINS-67982](https://issues.jenkins.io/browse/JENKINS-67982): Active Choice filtering not working for checkboxes and radio options