WooCommerce API Manager 3.4.1

* Tweak: Delete API Key activations when WooCommerce Subscription transitions to on-hold status.

* Notice: Declare incompatibility with WooCommerce HPOS until support is verified.
* Tweak: Detect WooCommerce Subscriptions included in WooCommerce core.
* Dev: Added wc_am_new_or_updated_order action hook that returns the order_id of a new or updated order containing API products.
* Dev: Can use WC_AM_API_RESOURCE_DATA_STORE()->get_all_api_resources_for_order_id( $order_id ) to get an array of all API Resource data created from the order line items. Use the plugins_loaded action hook to access the method.

* Feature: Added a product_list API endpoint which returns a unique list of product data such as Titles and Product IDs with no authentication required.
* Fix: get_human_time_diff() method returned slightly incorrect time for date.
* Fix: Order edit API Resources meta box > Activation Expires field displays only a date now rather than friendly messages such as "4 days", as friendly messages broke updates using a value that was not recognized as valid.
* Fix: Order edit API Resources meta box > Activation Expires help tip was displayed for WooCommerce Subscription when it should be hidden.
* Fix: Order edit API Resources meta box > Activation Expires field was updated when the Update button was clicked without changing the value manually. No update should have occurred.
* Tweak: Prevent Order edit API Resources meta box > Activation Expires field from being set to value less than current value.