update stuck err msg

Signed-off-by: Arvind Thirumurugan <arvindth@microsoft.com>

Author: Arvind Thirumurugan

pkg/controllers/updaterun/execution.go

@@ -589,14 +589,14 @@ func markUpdateRunProgressingIfNotWaitingOrStuck(updateRun placementv1beta1.Upda
 }
 
 // markUpdateRunStuck marks the updateRun as stuck in memory.
-func markUpdateRunStuck(updateRun placementv1beta1.UpdateRunObj, stageName, clusterName string) {
+func markUpdateRunStuck(updateRun placementv1beta1.UpdateRunObj, stageName, clusterNames string) {
 	updateRunStatus := updateRun.GetUpdateRunStatus()
 	meta.SetStatusCondition(&updateRunStatus.Conditions, metav1.Condition{
 		Type:               string(placementv1beta1.StagedUpdateRunConditionProgressing),
 		Status:             metav1.ConditionFalse,
 		ObservedGeneration: updateRun.GetGeneration(),
 		Reason:             condition.UpdateRunStuckReason,
-		Message:            fmt.Sprintf("The updateRun is stuck waiting for cluster %s in stage %s to finish updating, please check placement status for potential errors", clusterName, stageName),
+		Message:            fmt.Sprintf("The updateRun is stuck waiting for cluster/clusters %s in stage %s to finish updating, please check placement status for potential errors", clusterNames, stageName),
 	})
 }