fix: add empty role

Author: xovnsi

templates/header.hbs

@@ -18,7 +18,7 @@
         <li>{{link 'new_request' class='submit-a-request'}}</li>
         {{#unless signed_in}}
           <li>
-            {{#link "sign_in" class="sign-in"}}
+            {{#link "sign_in" class="sign-in" role=""}}
               {{t 'sign_in'}}
             {{/link}}
           </li>