Deprecate the random forest stuff

[bnb32]

          How would we feel about adding an issue to deprecate the random forest stuff? I don't think we ever use this. I think we built this originally when testing rf vs. dnn but at this point i think other libraries probably provide better rf abstractions and i just generally don't trust ours.

Originally posted by @grantbuster in https://github.com/NREL/phygnn/pull/57#discussion_r1961970380