cleanup: EphemeralContainers feature gate related codes

pkg/kubelet/kuberuntime/kuberuntime_container.go

@@ -116,7 +116,6 @@ func ephemeralContainerStartSpec(ec *v1.EphemeralContainer) *startSpec {
 // targeting. The target is stored as EphemeralContainer.TargetContainerName, which must be
 // resolved to a ContainerID using podStatus. The target container must already exist, which
 // usually isn't a problem since ephemeral containers aren't allowed at pod creation time.
-// This always returns nil when the EphemeralContainers feature is disabled.
 func (s *startSpec) getTargetID(podStatus *kubecontainer.PodStatus) (*kubecontainer.ContainerID, error) {
 	if s.ephemeralContainer == nil || s.ephemeralContainer.TargetContainerName == "" {
 		return nil, nil

pkg/kubelet/metrics/metrics.go

@@ -496,7 +496,7 @@ var (
 		&metrics.GaugeOpts{
 			Subsystem:      KubeletSubsystem,
 			Name:           ManagedEphemeralContainersKey,
-			Help:           "Current number of ephemeral containers in pods managed by this kubelet. Ephemeral containers will be ignored if disabled by the EphemeralContainers feature gate, and this number will be 0.",
+			Help:           "Current number of ephemeral containers in pods managed by this kubelet.",
 			StabilityLevel: metrics.ALPHA,
 		},
 	)