Polylang Pro 3.6.4

* Pro: Remove useless bulk translate action for ACF fields groups
* Pro: Fix the translation of the CPTUI labels when the language is set from the content
* Fix sitemaps redirected to the default language since WP 5.5.1
* Fix object cache not flushed for sticky posts #601
* Fix blog page broken when trashing a page and the blog page is not translated in all languages
* Fix custom flags ignored in WPML compatibility mode
* Fix breadcrumb for untranslated post types in Yoast SEO

* Honor install_languages capability to download language packs
* Pro: Fix integrations not loaded (with The Events Calendar, CPTUI, Content blocks)
* Pro: Fix fatal error with ACF if a flexible content includes a repeater and a relationship
* Pro: Fix terms sharing their slug impossible to update without changing the slug
* When available, use wpcom_vip_get_page_by_path() instead of get_page_by_path()
* Fix queries filtered when editing a post that was declared untranslatable after it got a language
* Fix issues with Yoast SEO 14.0+ (breadcrumbs, canonical, title and description)

* Pro: Fix posts sharing the same slug displayed on the same page
* Fix: Don't use a javascript localized string removed in WP 5.5 #568
* Fix fatal error in site health when no language is defined #563
* Fix various issues with Yoast SEO 14.x #65, #503, #505
* Fix fatal error with MU Domain Mapping when saving domains in Polylang settings #569