WooCommerce Product Search 6.1.0

* Fixes a comparison bug in the redirect_canonical filter used to avoid redirect loops in certain circumstances.
* Increased the implicit limit of items for category and attribute filter dropdowns (using 100000 to override the default used by the selectize component's maxOptions parameter).
* Added the woocommerce_product_search_selectize_max_options filter.

* WordPress 5.8 compatible.
* WooCommerce 5.9 compatible.
* Requires at least WooCommerce 5.5.
* Added the woocommerce_product_search_use_engine filter.
* Added compatibility with the WooCommerce Composite Products extension (skip handling its AJAX requests).

* WordPress 5.8 compatible.
* WooCommerce 5.8 compatible.
* Improved filter and search results consistency with Catalog Visibility options for products.
* Fixed limited processing when PHP memory_limit is set to -1 to have no memory limit.
* Fixed a PHP Notice when inconsistent data is encountered while indexing a product variation.
* Legacy widgets are not offered in the block editor as of this release by default.
* Added the WPS_LEGACY_WIDGETS constant which can be set to true to enable legacy widgets offered in the block editor.
* Fixed missing fill color in some block icons.
* Improved indexing schedule queries and reduced scheduling overhead.
* Fixed not applying weights on product filter search.
* Fixed query time logged twice on product filter search.
* Fixed blinker timeout set to 0 should disable it, for product search field and product filter search field.