ui: fix footer.html structure (#166)

packages/ui-default/templates/partials/footer.html

@@ -57,6 +57,7 @@
               <li class="menu__item"><a class="menu__link" href="{{ url('switch_language', lang=k) }}">{{ v }}</a></li>
             {%- endfor -%}
             </ol>
+          </li>
           <li class="footer__extra-link-item" data-dropdown-target="#menu-footer-theme">
             <span><span class="icon icon-global"></span> Theme <span class="icon icon-expand_less"></span></span>
             <ol class="dropdown-target menu" id="menu-footer-theme">