Cleanup: fix some CSS comment styles (especially copyrights)

chrome/browser/resources/chromeos/login/gaia_header.css

 /* Copyright 2015 The Chromium Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
+ * found in the LICENSE file. */
 
 :host {
   display: flex;
   flex-direction: column;
   justify-content: space-between;
 }
 
 #email {
   font-size: 20px;
 }