Add optional dependencies for cfdof workench to package.xml based on the upcoming major feature anounced regarding CFD studies

[luzpaz]

Per https://x.com/DavesRocketShop/status/1844743922947428491

When the time is right, a reminder that it would be helpful to add something like the following to the package.xml file:

<!-- Optional install of 3rd-party CfdOF workbench if utilizing CFD studies -->
<depend type="addon" optional="true">CfdOF Workbench</depend>

Giving the user a heads-up about this functionality. Apologies if I'm being to presumptuous and you knew this already.

[davesrocketshop]

Thanks. I'd already been thinking of this, but hadn't researched the optional tag yet. You saved me some digging :)

[luzpaz]

Great, that was the scenario that I was hoping to address!