add no swap as the default option for swap

Kubernetes-commit: 6a4e19a4ec9e11b77c9357375df4cadd8229836f

config/v1beta1/types.go

@@ -954,8 +954,8 @@ type ShutdownGracePeriodByPodPriority struct {
 
 type MemorySwapConfiguration struct {
 	// swapBehavior configures swap memory available to container workloads. May be one of
-	// "", "LimitedSwap": workload combined memory and swap usage cannot exceed pod memory limit
-	// "UnlimitedSwap": workloads can use unlimited swap, up to the allocatable limit.
+	// "", "NoSwap": workloads can not use swap, default option.
+	// "LimitedSwap": workload swap usage is limited. The swap limit is proportionate to the container's memory request.
 	// +featureGate=NodeSwap
 	// +optional
 	SwapBehavior string `json:"swapBehavior,omitempty"`