Panic with representation polymorphism and out-of-scope

Compiling the following code causes a panic in typeKind, even with the recent changes to representation polymorphism (fixing #23154 (closed))

module M where

import GHC.Exts

f = outOfScope :: (_ :: TYPE (r s))

This is probably best tackled after #20686, because just like #23051 (closed) it involves types whose kinds are ill-scoped.