EDD Software Licenses Uses Payment Date to generate license instead of Payment Completion Date

Bug Report

Apparently EDD Software Licenses uses Payment Date instead of Payment Completion Date to generate license keys.

includes/classes/class-edd-software-licensing.php
...
$license->create( $args['download_id'], $args['payment_id'], $price_id, $args['cart_index'], $options );

And...

includes/classes/class-sl-license.php
...
// Get the purchase date so we can set the correct license expiration date.
    $payment_meta  = $payment->get_meta();
    $purchase_date = null;
    if ( ! empty( $payment_meta['date'] ) ) {
        $purchase_date = strtotime( $payment_meta['date'], current_time( 'timestamp' ) );
    }
...
$expiration_date = strtotime( $license_length, $purchase_date );

Expected behaviour

It's expected that the license key use payment completion date so that they don't get expired unexpectedly.

Actual behaviour

If a customer completes an ancient order, the license key is generated for a back-date which is expired.

Steps to reproduce the behaviour

1) Create an order older than 1 year ago 2) Complete this order. 3) The license keys are expired. etc, etc

Information (if a specific version is affected):

PHP Version: 8*

EDD Version (or branch): 3*

WordPress Version: 6*

Any other relevant information:

awesomemotive / easy-digital-downloads