Fix about version check

Author: cedric-anne

templates/layout/parts/user_header.html.twig

@@ -120,7 +120,7 @@
                   <button type="button" class="btn-close" data-bs-dismiss="modal" aria-label="{{ __('Close') }}"></button>
                </div>
                <div class="modal-body">
-                  {% if not call('\Glpi\Toolbox\VersionParser::isStableRelease', [constant('GLPI_VERSION')]) %}
+                  {% if not call('\\Glpi\\Toolbox\\VersionParser::isStableRelease', [constant('GLPI_VERSION')]) %}
                       <div class='alert alert-important alert-warning d-flex'>
                         <strong>⚠️  {{ __("This version is UNSTABLE and some SECURITY FIXES may not be included.") }} ⚠️</strong>
                       </div>