added a todo comment

src/client/js/components/PasswordResetExecutionForm.jsx

@@ -14,6 +14,7 @@ const PasswordResetExecutionForm = (props) => {
           <div className="text-center">
             <h1><i className="icon-lock large"></i></h1>
             <h2 className="text-center">Reset Password</h2>
+            {/* TODO: show user email by GW-6778 */}
             <p>Enter a new password for hoge@example.com.</p>
             <form role="form" className="form" method="post">
               <div className="form-group">