YITH Infinite Scrolling Premium 1.29.0

* New: support for WooCommerce 5.1
* New: support for WordPress 5.7
* Update: plugin framework
* Fix: scroll top with "button" event
* Fix: compatibility issue with YITH WooCommerce Ajax Product Filter
* Dev: new filter 'yith_infs_scroll_restoration'

New: Support for WooCommerce 4.8
New: Support for WordPress 5.6
Update: Plugin framework
Update: Language files
Dev: New filter "yith_infinite_scrolling_load_frontend"

* New: Support for WooCommerce 4.4
* New: Support for WordPress 5.5
* Update: Plugin framework
* Update: Language files
* Tweak: Prevent window scrollRestoration event