Version 3.9.0

• Minimum required version of PHP is now 7.1.
• Performance improvements for the as_pending_actions_due() function.
• Existing filter hook action_scheduler_claim_actions_order_by enhanced to provide callbacks with additional information.
• Improved compatibility with PHP 8.4, specifically by making implicitly nullable parameters explicitly nullable.
• A large number of coding standards-enhancements, to help reduce friction when submitting plugins to marketplaces and plugin directories. Special props @crstauf for this effort.
• Minor documentation tweaks and improvements.