fix(argo-events): Align changelog structure (#1813)

relates to #1808

Was fixed already for [argo-cd](https://github.com/argoproj/argo-helm/pull/1810) and
[argo-workflows](https://github.com/argoproj/argo-helm/pull/1812)

Signed-off-by: jmeridth <jmeridth@gmail.com>

charts/argo-events/Chart.yaml

@@ -2,7 +2,7 @@ apiVersion: v2
 appVersion: v1.7.5
 description: A Helm chart for Argo Events, the event-driven workflow automation framework
 name: argo-events
-version: 2.1.1
+version: 2.1.2
 home: https://github.com/argoproj/argo-helm
 icon: https://argoproj.github.io/argo-events/assets/logo.png
 keywords:
@@ -15,4 +15,5 @@ maintainers:
     url: https://argoproj.github.io/
 annotations:
   artifacthub.io/changes: |
-    - "[Changed]: Update Argo Events to v1.7.5"
+    - kind: fixed
+      description: Align changelog structure to show changelogs on Artifact Hub