De-share the Handler struct in core API (#105979)

* De-share the Handler struct in core API

An upcoming PR adds a handler that only applies on one of these paths.
Having fields that don't work seems bad.

This never should have been shared.  Lifecycle hooks are like a "write"
while probes are more like a "read". HTTPGet and TCPSocket don't really
make sense as lifecycle hooks (but I can't take that back). When we add
gRPC, it is EXPLICITLY a health check (defined by gRPC) not an arbitrary
RPC - so a probe makes sense but a hook does not.

In the future I can also see adding lifecycle hooks that don't make
sense as probes.  E.g. 'sleep' is a common lifecycle request. The only
option is `exec`, which requires having a sleep binary in your image.

* Run update scripts

pkg/kubelet/kuberuntime/labels.go

@@ -67,7 +67,7 @@ type annotatedContainerInfo struct {
 	PodTerminationGracePeriod *int64
 	TerminationMessagePath    string
 	TerminationMessagePolicy  v1.TerminationMessagePolicy
-	PreStopHandler            *v1.Handler
+	PreStopHandler            *v1.LifecycleHandler
 	ContainerPorts            []v1.ContainerPort
 }
 
@@ -203,7 +203,7 @@ func getContainerInfoFromAnnotations(annotations map[string]string) *annotatedCo
 		klog.ErrorS(err, "Unable to get label value from annotations", "label", podTerminationGracePeriodLabel, "annotations", annotations)
 	}
 
-	preStopHandler := &v1.Handler{}
+	preStopHandler := &v1.LifecycleHandler{}
 	if found, err := getJSONObjectFromLabel(annotations, containerPreStopHandlerLabel, preStopHandler); err != nil {
 		klog.ErrorS(err, "Unable to get label value from annotations", "label", containerPreStopHandlerLabel, "annotations", annotations)
 	} else if found {