fix login request

ot_connect/Classes/Service/OtAuthenticationService.php

@@ -218,6 +218,7 @@ class OtAuthenticationService extends AbstractAuthenticationService
             $response = $this->apiService->request(
                 'POST',
                 self::LOGIN_URI,
+                [],
                 ['form_params' => ['_username' => $username, '_password' => $password]]
             );