feat(argo-events): Introduce chart signing (#2043)

Signed-off-by: Marco Kilchhofer <mkilchhofer@users.noreply.github.com>

charts/argo-events/Chart.yaml

@@ -2,7 +2,7 @@ apiVersion: v2
 appVersion: v1.7.6
 description: A Helm chart for Argo Events, the event-driven workflow automation framework
 name: argo-events
-version: 2.3.2
+version: 2.3.3
 home: https://github.com/argoproj/argo-helm
 icon: https://avatars.githubusercontent.com/u/30269780?s=200&v=4
 keywords:
@@ -14,6 +14,9 @@ maintainers:
   - name: argoproj
     url: https://argoproj.github.io/
 annotations:
+  artifacthub.io/signKey: |
+    fingerprint: 2B8F22F57260EFA67BE1C5824B11F800CD9D2252
+    url: https://argoproj.github.io/argo-helm/pgp_keys.asc
   artifacthub.io/changes: |
-    - kind: fixed
-      description: Use correct artifacthub kind and get latest chart version to artifacthub
+    - kind: added
+      description: Introduce chart signing