WooCommerce Bookings 2.2.0

* Add - Filter `woocommerce_bookings_product_defaults` to override default attributes for Product Booking.
* Fix - Ensure timeframe calculations are correct when using hours in the max bookable setting.
* Fix - Prevent duplication of transient keys.
* Fix - Revert "Add the jQuery UI styles and images to our codebase".

* Fix - Date correction for bookings that cross days between user's local timezone and site timezone.
* Tweak - WC 5.7 compatibility.

* Tweak - Introduced a new woocommerce_bookings_filter_time_slots filter to modify availability on a per-product basis.