bug#60511: 29.0.50; treesit-ready-p should not emit warning by default

[Stefan Kangas]

Severity: wishlist

This currently emits a warning if the ruby grammar is not installed:

    (treesit-ready-p 'ruby)

I think it should *not* emit a warning, as no other predicates in Emacs
do (e.g. `featurep', `integerp', etc.).

It could have an optional flag to emit a warning, if there's a strong
need for that.  But personally, I'd rather see a new function for that.

I also don't see much need for the `message' symbol as the second
argument, so I'd simplify the API by dropping that part.  It's currently
unused in our tree.