Capture Payment by posting to the APIService
using a valid ApiContext (See bootstrap.php for more on ApiContext)
The return object contains the status;
create payment to get authorization Id
get the authorization
Create a refund object indicating refund amount
Create a new apiContext object so we send a new PayPal-Request-Id (idempotency) header for this resource
Refund Capture Sample
This sample code demonstrate how you can process a refund on a Captured transaction created using the Capture API. API used: /v1/payments/capture/{}/refund