Issue informative warning if user tries to use `evaluate!(::MLJModel, ...)` instead of `evaluate(::MLJModel, ...)`.

[ablaom]

[DilumAluthge]

Probably the correct way to do this is to register a "hint": https://docs.julialang.org/en/v1/base/base/#Base.Experimental.register_error_hint

[ablaom]

Didn't know about this feature, thanks. That's a pattern I've wondered about. Guess it has to wrapped in a block to test the feature actually exists, as it is still marked experimental. PR welcome 😉