public async void When_Trigger_And_NextPaymentDateIsNull()
        {
            // Arrange

            var nextPaymentDateCalculateOptions =
                new NextPaymentDateCalculateOptions
            {
                NextPaymentDate = null
            };

            var httpRequestHeaders =
                new HeaderDictionary
            {
                { "Content-Type", "application/json" }
            };

            var httpRequest =
                HttpRequestHelper.CreateHttpRequest(
                    "POST",
                    "http://localhost",
                    httpRequestHeaders,
                    nextPaymentDateCalculateOptions);

            // Act

            var actionResult =
                await NextPaymentDateCalculateHttpTrigger.Run(
                    httpRequest,
                    _logger);

            // Assert

            var okObjectResult =
                (OkObjectResult)actionResult;

            var nextPaymentDate =
                (DateTime)okObjectResult.Value;

            var expectedNextPaymentDate =
                DateTime.UtcNow.Date.AddDays(2);

            nextPaymentDate.Date.Should().Be(expectedNextPaymentDate);
        }
        public async void When_Trigger()
        {
            // Arrange

            var nextPaymentDate =
                _faker.Date.Soon();

            var nextPaymentDateCalculateOptions =
                new NextPaymentDateCalculateOptions
            {
                NextPaymentDate = nextPaymentDate
            };

            var httpRequestHeaders =
                new HeaderDictionary
            {
                { "Content-Type", "application/json" }
            };

            var httpRequest =
                HttpRequestHelper.CreateHttpRequest(
                    "POST",
                    "http://localhost",
                    httpRequestHeaders,
                    nextPaymentDateCalculateOptions);

            // Act

            var actionResult =
                await NextPaymentDateCalculateHttpTrigger.Run(
                    httpRequest,
                    _logger);

            // Assert

            actionResult.Should().BeOfType(typeof(OkObjectResult));

            var okObjectResult =
                (OkObjectResult)actionResult;

            okObjectResult.Value.Should().BeOfType(typeof(DateTime));
        }