Documentation: Update link to new forum on admin page and menu block

app/home/home_menu.html

@@ -1 +1 @@
-<li class="forum-btn"><a href="http://www.chamilo.org/forum" target="_self">Forum</a></li>
+<li class="forum-btn"><a href="https://chamilo.org/en/forum" target="_self">Forum</a></li>

main/admin/index.php

@@ -932,7 +932,7 @@ if (api_is_platform_admin()) {
     ];
     $items[] = [
         'class' => 'item-forum',
-        'url' => 'https://forum.chamilo.org/',
+        'url' => 'https://chamilo.org/en/forum',
         'label' => get_lang('ChamiloForum'),
     ];
     $items[] = [