feat: Add AWS EKS ARN support for remote cluster name (#7161)

* feat: Add AWS EKS ARN support for remote cluster name

- Extend validation to allow AWS EKS ARN format for REMOTE_CLUSTER_NAME
- Extract cluster name from ARN if REMOTE_CLUSTER_NAME is in ARN format
- Update error messages to reflect new validation rules

* fix: Add AWS EKS ARN support for remote cluster name

* fix: regex for AWS eks

* Refactor: AWS EKS ARN regex pattern in kiali-prepare-remote-cluster.sh

* Refactor: Remove unnecessary echo statement in create_kiali_remote_cluster_secret() function

hack/istio/multicluster/kiali-prepare-remote-cluster.sh

@@ -245,6 +245,13 @@ create_kiali_remote_cluster_secret() {
     local cert_auth_yaml="certificate-authority-data: ${remote_cluster_ca_bytes}"
   fi
 
+  # Check if the REMOTE_CLUSTER_NAME matches the AWS EKS ARN regex pattern.
+  # If it does, extract the cluster name from the ARN and assign it back to REMOTE_CLUSTER_NAME.
+  AWS_REGION_REGEX='(us|eu|ap|sa|ca|me|af|il|us-gov)-(north|south|east|west|central|southeast|northeast)-[0-9]'
+  AWS_EKS_ARN_REGEX="arn:aws:eks:${AWS_REGION_REGEX}:[0-9]{12}:cluster/([0-9A-Za-z][_A-Za-z0-9\-]{0,99})$"
+  if echo "${REMOTE_CLUSTER_NAME}" | grep -Eq "${AWS_EKS_ARN_REGEX}"; then
+      REMOTE_CLUSTER_NAME=$(echo "${REMOTE_CLUSTER_NAME}" | sed 's/^.*:cluster\/\(.*\)$/\1/')
+  fi
   # a Secret stringData key must conform to Kubernetes naming rules. Othewise, this kind of error will result:
   #    a valid config key must consist of alphanumeric characters, '-', '_' or '.'
   #    (e.g. 'key.name',  or 'KEY_NAME',  or 'key-name', regex used for validation is '[-._a-zA-Z0-9]+')