Added

• Add Support for PHP 8 This adapter can now be installed with PHP 8, even though Guzzle 6 is not tested on PHP 8. If you need a PSR-18 client, use Guzzle 7 which natively implements PSR-18. If you need the HTTPlug interfaces for asynchronous calls or for a system that still requires HTTPlug, use the guzzle7-adapter instead of this repository.