* Tweak-PHP 8 compatibility.

* New: Purchase Course block
* Add Purchase Course block-#543
* Add single product front-end rendering-#544
* Use proper filter to extend Take Course block-#545
* Add product cards to the purchase block in the editor-#546
* Use product data for the Purchase Button block in the editor-#547
* Add multiple products to the frontend-#548
* Add purchase block keywords-#550
* Add legacy course method check to avoid fatal error on sites running old Sensei version-#551
* Show button only when in block preview mode-#552
* Fix text domain-#554
* Warn learner when buying a product containing a course they are already taking-#549
* Expand the editor and the frontend to support many purchase blocks-#553
* Ensure variable products work with purchase block-#555
* Tweak: Switch to webpack via wordpress-scripts and simplify build-#522
* Fix: Fix typo in package generation to include `lang` folder-#558
* Sensei LMS: Version bump to 3.6.0 https://raw.githubusercontent.com/Automattic/sensei/version/3.6.0/changelog.txt