WooCommerce Subscriptions 7.3.1

* Add: Compatibility with WooCommerce's new preview email feature introduced in 9.6.
* Fix: Prevents PHP fatal error when wcs_can_user_renew_early() is called with a non-existent subscription ID.
* Fix: Prevent payment gateways that complete Change Payment requests asynchronously from blocking future attempts to update payment methods for all subscriptions.
* Fix: Resolved an issue that could lead to undefined variable when attempting to send a customer notification email with no order.
* Fix: Prevents the customer's postal code being used as their billing city in the current session, following a change to payment details.
* Dev: Use the subscription's customer ID during the `wcs_can_user_renew_early()` function call when sending customer notification emails.
* Dev: Fix PHP deprecated warnings caused by calling esc_url with null.
* Dev: Update subscriptions-core to 7.9

* Fix: Prevent failing non-recent renewal order from suspending the subscription and marking the most recent renewal order as failed.
* Fix: Use block theme-styled buttons for subscription and related-orders actions on My Account pages.
* Fix: Subscription totals not properly updating when customers remove items via the My Account > View Subscription page on some stores with caching enabled.
* Fix: Resolved unexpected errors during the renewal process when a subscription contains metadata with key "id".
* Update: Changed the link on the order thank-you page to take customers directly to their "My Account > Subscriptions" page.
* Dev: Update subscriptions-core to 7.8.0

6.9.0