Update vendor files to point to kubernetes-1.12.0-beta.1

vendor/k8s.io/apimachinery/pkg/test/zz_generated.deepcopy.go

@@ -33,9 +33,7 @@ func (in *List) DeepCopyInto(out *List) {
 		in, out := &in.Items, &out.Items
 		*out = make([]runtime.Object, len(*in))
 		for i := range *in {
-			if (*in)[i] == nil {
-				(*out)[i] = nil
-			} else {
+			if (*in)[i] != nil {
 				(*out)[i] = (*in)[i].DeepCopyObject()
 			}
 		}