fix(dropdownfield): add security token for GLPI 9.5.3

Signed-off-by: Thierry Bugier <tbugier@teclib.com>

Author: btry

inc/field/dropdownfield.class.php

@@ -377,6 +377,9 @@ public function getRenderedHtml($canEdit = true): string {
       if (!empty($this->question->fields['values'])) {
          $dparams = $this->buildParams($rand);
          $dparams['display'] = false;
+         if (version_compare(GLPI_VERSION, '9.5.3') >= 0) {
+            $params['_idor_token'] = Session::getNewIDORToken(User::getType());
+         }
          $html .= $itemtype::dropdown($dparams);
       }
       $html .= PHP_EOL;