Update page title to h1

VAN-179

lms/templates/student_account/password_reset.underscore

 <div class="js-form-feedback" aria-live="assertive" tabindex="-1">
 </div>
 
-<h2><%- gettext("Password assistance") %></h2>
+<h1><%- gettext("Password assistance") %></h1>
 
 <form id="password-reset" class="password-reset-form" tabindex="-1" method="POST">