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

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

@@ -0,0 +1,16 @@
+// 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 spotify provides constants for using OAuth2 to access Spotify.
+package spotify // import "golang.org/x/oauth2/spotify"
+
+import (
+	"golang.org/x/oauth2"
+)
+
+// Endpoint is Spotify's OAuth 2.0 endpoint.
+var Endpoint = oauth2.Endpoint{
+	AuthURL:  "https://accounts.spotify.com/authorize",
+	TokenURL: "https://accounts.spotify.com/api/token",
+}