Fatal error after enabling http_client_manager_example

Problem/Motivation

After installing http_client_manager_example via interface or drush, site will throw an error as below:
Fatal error: Declaration of Guzzle\Service\Loader\FileLoader::load($resource, $type = null) must be compatible with Symfony\Component\Config\Loader\LoaderInterface::load(mixed $resource, ?string $type = null): mixed in /var/www/html/<site name>/vendor/arthurkirkosa/guzzle-description-loader/src/FileLoader.php on line 19

Steps to reproduce

Install http_client_manager_example either using interface or drush.

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes