firstboot: Hide left menu during first boot as intended

This seems to be a regression from earlier behavior.

Signed-off-by: Sunil Mohan Adapa <sunil@medhas.org>
Reviewed-by: Joseph Nuthalapati <njoseph@riseup.net>

plinth/modules/first_boot/templates/base_firstboot.html

@@ -28,6 +28,9 @@
   </style>
 {% endblock %}
 
+{% block mainmenu_left_collapse %}
+{% endblock %}
+
 {% block mainmenu_right %}
   {% if user.is_authenticated %}
     {% include "firstboot_navbar.html" %}

plinth/templates/base.html

@@ -108,6 +108,7 @@
       </div>
       <div class="collapse navbar-collapse">
         <ul class="nav navbar-nav">
+          {% block mainmenu_left_collapse %}
             {% if user.is_authenticated and user_is_admin %}
               <li>
                 {% url 'index' as index_url %}
@@ -136,6 +137,7 @@
                 </a>
               </li>
             {% endif %}
+          {% endblock %}
         </ul>
         <ul class="nav navbar-nav navbar-right">
           {% block mainmenu_right %}