Update Helm chart version to 4.28.0 for GitHub Pages release

Author: rcourtman

deploy/helm/pulse/Chart.yaml

@@ -2,8 +2,8 @@ apiVersion: v2
 name: pulse
 description: Helm chart for deploying the Pulse hub and optional Docker monitoring agent.
 type: application
-version: 4.26.4
-appVersion: "4.26.4"
+version: 4.28.0
+appVersion: "4.28.0"
 icon: https://raw.githubusercontent.com/rcourtman/Pulse/main/docs/images/pulse-logo.svg
 keywords:
   - monitoring