Update generic-yearly-gantt-chart-with-today.json

[DRVRogo]

Update to generic-yearly-gantt-chart-with-today.json

Q	A
Bug fix?	no
New sample?	no
Related issues?

What's in this Pull Request?

Updates generic-yearly-gantt-chart-with-today.json so that the Gantt chart now correctly renders when Start and End dates are outside the timeframe of the current year. That is, if the Start and/or End dates are before 1st January of current year, as well as if Start and/or End dates are after 31st December of current year.

[tecchan1107]

Thank you for the update and for sending the pull request @DRVRogo 🙏✨ One point of concern is noted in the following. If possible, I would appreciate a reply.