public void ValidateMethodHappyPath()
        {
            var cloudEvent = new PartitionedEvent
            {
                Type         = "MyType",
                Source       = "/MySource",
                PartitionKey = "123"
            };

            cloudEvent.Invoking(ce => ce.Validate())
            .Should().NotThrow();
        }
        public void ValidateMethodSadPath(string partitionKey)
        {
            var cloudEvent = new PartitionedEvent
            {
                Type         = "MyType",
                Source       = "/MySource",
                PartitionKey = partitionKey
            };

            cloudEvent.Invoking(ce => ce.Validate())
            .Should().ThrowExactly <CloudEventValidationException>()
            .WithMessage("PartitionKey cannot be null or empty.");
        }