Update go-github library

vendor/github.com/google/go-github/example/migrations/main.go

@@ -0,0 +1,41 @@
+// Copyright 2018 The go-github AUTHORS. All rights reserved.
+//
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// migrations demonstrates the functionality of
+// the user data migration API for the authenticated GitHub
+// user and lists all the user migrations.
+package main
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/google/go-github/v19/github"
+	"golang.org/x/oauth2"
+)
+
+func fetchAllUserMigrations() ([]*github.UserMigration, error) {
+	ctx := context.Background()
+	ts := oauth2.StaticTokenSource(
+		&oauth2.Token{AccessToken: "<GITHUB_AUTH_TOKEN>"},
+	)
+	tc := oauth2.NewClient(ctx, ts)
+	client := github.NewClient(tc)
+
+	migrations, _, err := client.Migrations.ListUserMigrations(ctx)
+	return migrations, err
+}
+
+func main() {
+	migrations, err := fetchAllUserMigrations()
+	if err != nil {
+		fmt.Printf("Error %v\n", err)
+		return
+	}
+
+	for i, m := range migrations {
+		fmt.Printf("%v. %v", i+1, m.GetID())
+	}
+}