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

vendor/golang.org/x/oauth2/mailchimp/mailchimp.go

@@ -0,0 +1,17 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package mailchimp provides constants for using OAuth2 to access MailChimp.
+package mailchimp // import "golang.org/x/oauth2/mailchimp"
+
+import (
+	"golang.org/x/oauth2"
+)
+
+// Endpoint is MailChimp's OAuth 2.0 endpoint.
+// See http://developer.mailchimp.com/documentation/mailchimp/guides/how-to-use-oauth2/
+var Endpoint = oauth2.Endpoint{
+	AuthURL:  "https://login.mailchimp.com/oauth2/authorize",
+	TokenURL: "https://login.mailchimp.com/oauth2/token",
+}