Added another category of personal information to the personal-information page, after review of personal information in the code. Completes issue ietf-tools#2501.

 - Legacy-Id: 15150

Author: levkowetz

ietf/templates/help/personal-information.html

@@ -76,6 +76,7 @@ <h1>Personal Information in the Datatracker</h1>
      <li>Personal biography;</li>
      <li>Personal email addresses not derived from IETF contributions; and </li>
      <li>Personal account login information</li>
+     <li>Personal notification subscriptions</li>
    </ul>
 
    <p>