Update CHANGELOG

CHANGELOG.md

@@ -7,6 +7,9 @@ All notable changes to this project will be documented in this file.
 * The rule form permits to add Search Query to the event definition description ([issue #124](https://github.com/airbus-cyber/graylog-plugin-alert-wizard/issues/124))
 
 Note : This feature involves an internal updating of the API. The rules must be exported and deleted then imported with the new version of the plugin.
+### Changes
+* Remove severity and use event definition priority ([issue #100](https://github.com/airbus-cyber/graylog-plugin-logging-alert/issues/100))
+
 
 ## [5.2.1](https://github.com/airbus-cyber/graylog-plugin-alert-wizard/compare/5.2.0...5.2.1)
 ### Bug Fixes