* Added new added order item to existing order will trigger course enrollment
* Fixed retroactive tool and some variables are not compatible with WC 5.6
* Fixed retroactive tool doesn't honor the expired subscription course removal setting
* Fixed renewal subscription payment reset access date for expired courses
* Updated use global variable instead of debug backtrace to enable subscription products filter
* Fixed conflict with WooCommerce product bundle extension, better code logic
* Fixed typo in get_type method name
* Added a setting to skip disabling course access on subscription expiry
* Added an action hook to remove course access for failed and cancelled subscriptions
* Fixed subscription renewal changing the course enrollment date
* Fixed pricing fields missing on the product edit page
