(REF) E2E_Extern_*RestTest - Extract `isOldQSupported()` as well as `rest.php?q=civicrm/ENTITY/ACTION`. ...extends `BaseRestTest` and targets `civicrm/ajax/rest`. It only tests `civicrm/ajax/rest?entity=ENTITY&action... (`q=civicrm/ajax/rest&q=civicrm/ENTITY/ACTION...