WooCommerce Product Reviews Pro 1.20.0

* New - Added support for new WooCommerce email previews
* Dev - Update the SV Plugin Framework to v5.15.6

* Fix: Remove support for deprecated navigation feature
* Fix: "Flags" meta boxes not appearing when editing a reply to a review from WP-Admin

* Fix: Address "Creation of dynamic property" deprecation warnings in PHP 8.2+.
* Fix: Address "Passing null to parameter of type string" deprecation warnings in PHP 8.1+.