public void Given_DateTimeOffset_WhenAsIso8601IsInvoked_ThenExpectedStringIsBeingReturned(
            int year,
            int month,
            int day,
            int hour,
            int minute,
            int second,
            int millisecond,
            string expected)
        {
            // Arrange
            var dateTimeOffset = new DateTimeOffset(year, month, day, hour, minute, second, millisecond, TimeSpan.Zero);

            // Act
            var actual = dateTimeOffset.AsIso8601();

            // Assert
            actual.Should().Be(expected);
        }