[Feature Request] Research/add model for Virtual Challenge

[mattmanley]

Is your feature request related to a problem? Please describe.
It seems like it would be helpful to have a model for a virtual challenge since the process for creating one is different from the process for creating non-virtual challenges. See here and here.

Describe the solution you'd like
A model with the appropriate properties should be added.

Describe alternatives you've considered
The use could potentially create this object themselves, but it might be more difficult.

Additional context
N/A