[Feature Request] Add support for retrieving task action statistics for a given challenge

[mattmanley]

Is your feature request related to a problem? Please describe.
Users should be able to easily retrieve task action statistics for a given challenge using the data/challenge/{id} endpoint. Although this is not a documented endpoint, it is useful for quickly returning summary statistics for a challenge.

Describe the solution you'd like
Support the data/challenge/{id} endpoint.

Describe alternatives you've considered
N/A

Additional context
N/A