move IPv6DualStack feature to stable. (#104691)

* kube-proxy

* endpoints controller

* app: kube-controller-manager

* app: cloud-controller-manager

* kubelet

* app: api-server

* node utils + registry/strategy

* api: validation (comment removal)

* api:pod strategy (util pkg)

* api: docs

* core: integration testing

* kubeadm: change feature gate to GA

* service registry and rest stack

* move feature to GA

* generated

pkg/util/iptables/testing/fake.go

@@ -176,4 +176,8 @@ func (f *FakeIPTables) HasRandomFully() bool {
 	return f.hasRandomFully
 }
 
+func (f *FakeIPTables) Present() bool {
+	return true
+}
+
 var _ = iptables.Interface(&FakeIPTables{})