Bump matrix chart to 2.9.0

Author: remram44

charts/matrix/Chart.yaml

@@ -4,7 +4,7 @@ description: A chart for Matrix.org, includes Synapse, PostgreSQL, and Element.
 
 type: application
 
-version: 2.8.1
+version: 2.9.0
 
 # The version of Synapse
 appVersion: "1.138.0"