Fix "Call to a member function getTotalItems() on null"

Closes #3477320

modules/graphql_compose_views/src/Plugin/GraphQL/DataProducer/ViewsPageInfo.php

@@ -43,7 +43,7 @@ class ViewsPageInfo extends DataProducerPluginBase {
       'offset' => $view->getOffset() ?: 0,
       'page' => $view->getCurrentPage() ?: 0,
       'pageSize' => $view->getItemsPerPage() ?: 0,
-      'total' => $view->pager->getTotalItems() ?: 0,
+      'total' => $view->total_rows ?: 0,
     ];
   }