Use the new KC createdTimestamp property for integrity check

The previous legacy_created was a workaround. Now it is native in KC, kudos to heddn for helping with that upstream.

Closes #3436607

drupalorg/includes/KeycloakIntegration.php

@@ -227,7 +227,7 @@ class KeycloakIntegration {
         throw new \Exception(sprintf('uid: %s Keycloak(%s=%s) does not match Drupal(%s=%s)', $uid, $kc_name, $kc_record[$kc_name], $drupal_name, $drupal_result[$drupal_name]));
       }
     }
-    if ($kc_record['attributes']['legacy_created'][0]/1000 !== (int) $drupal_result['created']) {
+    if ($kc_record['createdTimestamp']/1000 !== (int) $drupal_result['created']) {
       throw new \Exception(sprintf('uid: %s Keycloak(legacy_created=%s) does not match Drupal(created=%s)', $uid, $kc_record['legacy_created'], $drupal_result['created']));
     }
     if (empty($kc_record['totp']) && !empty($drupal_result['tfa'])) {