public async Task ServiceUnavailableJsonClientError()
        {
            var error = ServiceErrors.CreateServiceUnavailable();

            var service = CreateTestService(request =>
            {
                var response     = new HttpResponseMessage(HttpStatusCode.ServiceUnavailable);
                response.Content = new StringContent($"{{\"code\":\"{error.Code}\",\"message\":\"{error.Message}\"}}");
                response.Content.Headers.ContentType = MediaTypeHeaderValue.Parse(HttpServiceUtility.JsonMediaType);
                return(response);
            });

            var result = await service.CreateWidgetAsync(new WidgetDto(name : "hi"));

            result.Error.Should().BeDto(error);
        }