Elementor Pro 3.21.1

* Fix: Removed duplicate Custom CSS section ([#3938](BUG - duplicated custom style in setting page panel · Issue #3938 · pojome/elementor))
* Fix: `box-shadow` issue with cards skin ([#3940]([bug] shadow for post widget cut off · Issue #3940 · pojome/elementor))

* Fix: Added global widget compatibility for Elementor v2.0
* Fix: Reduced API request for some servers

* Tweak: Allow brackets in phone field
* Tweak: Added compatibility with Yoast 7.0.+
* Tweak: Added compatibility for the future release of Elementor v2.0
* Fix: Support for multiple carousel setting in editor
* Fix: `on_export` issue in forms widget