chore(argo-rollouts): Update dependency argoproj/argo-rollouts to v1.8.4 (#3728)

Signed-off-by: argoproj-renovate[bot] <161757507+argoproj-renovate[bot]@users.noreply.github.com>
Co-authored-by: argoproj-renovate[bot] <161757507+argoproj-renovate[bot]@users.noreply.github.com>

Author: argoproj-renovate[bot]

charts/argo-rollouts/Chart.yaml

@@ -1,8 +1,8 @@
 apiVersion: v2
-appVersion: v1.8.3
+appVersion: v1.8.4
 description: A Helm chart for Argo Rollouts
 name: argo-rollouts
-version: 2.40.5
+version: 2.40.6
 home: https://github.com/argoproj/argo-helm
 icon: https://argoproj.github.io/argo-rollouts/assets/logo.png
 keywords:
@@ -19,4 +19,4 @@ annotations:
     url: https://argoproj.github.io/argo-helm/pgp_keys.asc
   artifacthub.io/changes: |
     - kind: changed
-      description: use named port for service
+      description: Bump argo-rollouts to v1.8.4