Fix undefined index

inc/commonglpi.class.php

@@ -1196,7 +1196,7 @@ class CommonGLPI {
       // Init active tab to main if not defined
       if (!isset($_SESSION['glpi_tabs'][self::getType()])) {
          // TODO: use array_key_first when php 7.3 is supported
-         $tabs = array_keys($this->defineTabs());
+         $tabs = array_keys($this->defineAllTabs());
          $first_tab = array_shift($tabs);
          if ($first_tab) {
             Session::setActiveTab(self::getType(), $first_tab);