code: public function persistCatSession($catSession, RouteItem $routeItem = null)
      {
          return $this->getServiceManager()->get(CatService::SERVICE_ID)->persistCatSession(
              $catSession,
              $this->getTestSession(),
              $this->getCompilationDirectory()['private'],
              $routeItem
          );
      }
docs: Persist the CAT Session Data.
  
  Persist the current CAT Session Data in storage.
  
  @param string $catSession JSON encoded CAT Session data.
  @param RouteItem|null $routeItem
  @return mixed