BookingWP WooCommerce Appointments 4.21.0

* Improvement - Clear cache only when post object is defined for the appointments.
* Improvement - Improved compatibility with Polylang for WooCommerce.
* Improvement - Fixed strings to Hebrew translation.
* Improvement - Updated Product Add-ons to 7.1.0.
* Improvement - Updated all translations and adjusted add-ons strings.
* Improvement - Compatibility with WooCommerce 9.3.
* Improvement - Use pretty uniform pretty time duration display.
* Improvement - SMS "Customer Confirmation message" missing info.
* Improvement - Removed option to edit order inside appointment edit screen in admin.
* Improvement - Added filter to allow not updating gCal description on appointment update.
* Improvement - Updated php rrule to 2.5.1.
* Fix - PHP 8.2 error when empty array present.
* Fix - Recurring events in gCal not blocking out times.
* Fix - gCal recurring event blocking out the wrong time.

* Feature - Added WC Payments multicurrency support.
* Feature - Added Appointable product to Analytics for filtering.
* Improvement - Better integration with WooCommerce Payments gateway.
* Improvement - Add-ons integration added earlier, better compatibility with external plugins.
* Improvement - Updated Product Add-ons to 6.8.4.
* Improvement - Handling failed orders with appointments added back with additional validations.
* Improvement - Bump "WC requires at least" to version 8.7.
* Improvement - Compatibility with WooCommerce 9.0.
* Fix - Add-ons work with WC Payments for appointable products.
* Fix - Updating manually added Appointment in Order can create critical error.
* Fix - Timezone visible in admin for non-timezone appointments.

* Improvement - Simplified each order item ID call to speed the query.
* Fix - Blocks for appointments not loading, remove version checking as core supports it.
* Fix - Exporting admin created appointments with tax is wrong.

* Improvement - Hidden input forms don't need a label.
* Improvement - Prevent quantity editing for appointable products.
* Fix - Adding appointment in admin to existing order not working.
* Fix - Adding appointment in admin redirect is wrong.

* Fix - Do not cancel unpaid orders.