Add cookies consent banner

Allow enabling from settings admin section.

Note that we set the z-index to 20 in order to will be greater than
the others z-index elements in the application like <header> on
mobile devices.

app/views/admin/settings/_filter_subnav.html.erb

@@ -42,15 +42,20 @@
   </li>
 
   <li class="tabs-title" id="remote-census-tab">
-   <%= link_to "#tab-remote-census-configuration" do %>
+    <%= link_to "#tab-remote-census-configuration" do %>
       <%= t("admin.settings.index.remote_census.title") %>
     <% end %>
   </li>
 
   <li class="tabs-title" id="sdg-tab">
-   <%= link_to "#tab-sdg-configuration" do %>
+    <%= link_to "#tab-sdg-configuration" do %>
       <%= t("admin.settings.index.sdg.title") %>
     <% end %>
   </li>
 
+  <li class="tabs-title" id="cookies-consent-tab">
+    <%= link_to "#tab-cookies-consent" do %>
+      <%= t("admin.settings.index.cookies_consent.title") %>
+    <% end %>
+  </li>
 </ul>

app/views/admin/settings/index.html.erb

@@ -33,4 +33,8 @@
   <div class="tabs-panel" id="tab-sdg-configuration">
     <%= render Admin::Settings::SDGConfigurationTabComponent.new %>
   </div>
+
+  <div class="tabs-panel" id="tab-cookies-consent">
+    <%= render Admin::Settings::CookiesConsentTabComponent.new %>
+  </div>
 </div>