对外提供退款DTO(对外提供退款DTO)

{
    "appId": "string",
    "businessId": "string",
    "channelExtra": "string",
    "channelPayOrderNo": "string",
    "extJsonb": {},
    "mchOrderNo": "string",
    "mchRefundNo": "string",
    "notifyUrl": "string",
    "refundAmount": "string",
    "refundMode": "string",
    "refundReason": "string",
    "reqTime": "string",
    "sign": "string",
    "tenantId": "string"
}