Woocommerce GoCardless 2.8.2

* Add – Cancel subscription if the payment is cancelled when a subscriber cancels the mandate.
* Dev – Remove WooThemes updater.
* Tweak – Bump WooCommerce tested up to 7.3.0

* Dev - Add linting, unit and e2e test coverage within GitHub Actions.
* Add - Support for High-performance Order Storage ("HPOS") (formerly known as Custom Order Table, "COT").

* Fix - Bug that would hide Go Cardless when WooCommerce Pre-Orders was active
* Tweak - WP tested up to 5.8.
* Tweak - WC tested up to 6.0