Verify payment service credentials

using Gr4vy;
using Gr4vy.Models.Components;
using System.Collections.Generic;

var sdk = new Gr4vySDK(
    id: "example",
    server: SDKConfig.Server.Sandbox,
    bearerAuthSource: Auth.WithToken(privateKey),
    merchantAccountId: "default"
);

var res = await sdk.PaymentServices.VerifyAsync(verifyCredentials: new VerifyCredentials() {
    PaymentServiceDefinitionId = "stripe-card",
    Fields = new List<Field>() {},
});

// handle response

"<any>"