update the description of hub-spoke-shared

Signed-off-by: Carlos Santana <csantana23@gmail.com>

Author: csantanapr

argocd/iac/terraform/examples/eks/multi-cluster/hub-spoke-shared/README.md

@@ -1,4 +1,4 @@
-# Multi-Cluster centralized hub-spoke topology
+# Multi-Cluster centralized hub-spoke topology (shared responsability)
 
 This example deploys ArgoCD on the Hub cluster (ie. management/control-plane cluster).
 The spoke clusters are registered as remote clusters in the Hub Cluster's ArgoCD
@@ -7,6 +7,10 @@ Each spoke cluster have ArgoCD only use for workloads, not the addons
 
 Each spoke cluster gets deployed an app of apps ArgoCD Application with the name `workloads-${env}`
 
+This platform team and the application team have a **shared** responsability of the cluster's GitOps configuration with multiple instances of ArgoCD targeting the same cluster,
+the platform team responsible of the cluster addons using the ArgoCD instance on the hub cluster and the application team responsible of the workloads using the ArgoCD instance on the spoke cluster.
+
+
 Deploy the Hub Cluster
 ```shell
 cd hub