License key is not saved to pass data during activation

[robincornett]

Bug Report

Expected behavior

When I activate a pass' license key, I expect the license key to be added to the edd_pass_licenses option data, per the code:

easy-digital-downloads/includes/class-edd-license-handler.php

Lines 251 to 255 in 16b95fd

	if ( ! empty( $api_data->pass_id ) && ! empty( $api_data->license ) && 'valid' === $api_data->license ) {
	$passes[ $license ] = array(
	'pass_id' => intval( $api_data->pass_id ),
	'time_checked' => time()
	);

Actual behavior

When I activate a license, the $license variable for the array key is not defined. During activation, the class property for the license is not set, so we need to use the key that's being evaluated/saved to the database.

Steps to reproduce the behavior

1. Activate a license for any pass.
2. Check the edd_pass_licenses data in the database. The pass ID and timestamp will be saved, but without the license key.

Information (if a specific version is affected):

PHP Version: 7.4
EDD Version (or branch): master
WordPress Version: 5.8