get https://{cluster}.voucherify.io/v1/vouchers/
Retrieves the voucher with the given code or unique Voucherify ID. You can either pass the voucher ID which was assigned by Voucherify, e.g., v_7HxHkf4VAkMuc8u4lZs78lyRwhRze5UE, or the code of the voucher as the path parameter value, e.g., 7fjWdr.