post https://testflight.tremendous.com/api/v2/order_approvals//approve
Approves an order that is pending review, identified by the given id in the URL.
Approvals is a feature that requires orders to be approved by an organization admin
before they are sent out. To enable approvals for your organization, please enable
'Allow approvals via API' via the organization''s 'Order Approvals' settings from the Tremendous dashboard.