Update Helm release alertmanager to v1.22.0

Author: renovate[bot]

monitoring/argo-apps/alertmanager.yaml

@@ -11,7 +11,7 @@ spec:
       targetRevision: HEAD
       ref: myRepo # repo is available via symlink "myRepo"
     - repoURL: https://prometheus-community.github.io/helm-charts
-      targetRevision: 1.14.0
+      targetRevision: 1.22.0
       chart: alertmanager
       helm:
         valueFiles: