Remove redundant TODO comment

At the moment, we use this function only when `n` is dynamic (part of the
parse), and so this cannot be made statically allocated. If we ever need
that, we could create an `n_of_const` combinator separately or something.

aml/src/parser.rs

@@ -168,7 +168,6 @@ where
     }
 }
 
-// TODO: can we use const generics (e.g. [R; N]) to avoid allocating?
 pub fn n_of<'a, 'c, P, R>(parser: P, n: usize) -> impl Parser<'a, 'c, Vec<R>>
 where
     'c: 'a,