Generate an account activation URL for a customer whose account is not yet enabled. This is useful when you've imported a large number of customers and want to send them activation emails all at once. Using this approach, you'll need to generate and send the activation emails yourself.The account activation URL generated by this endpoint is for one-time use and will expire after 30 days. If you make a new POST request to this endpoint, then a new URL will be generated. The new URL will be again valid for 30 days, but the previous URL will no longer be valid.