build: update npm dependencies

tools/gulp-tasks/build.js

@@ -1,3 +1,10 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
 
 module.exports = {
   // build everything and generate bundles