Array repeat exprs dont permit non-copy adt ctors as elements

[BoxyUwU]

I tried this code:

fn main() {
  struct Foo;
  [Foo; 2];
}

I expected to see this happen: it works because we attempt to permit paths to const items as repeat expr elements without Copy holding. It's also trivial to just write [const { Foo }; 2] so the lack of expressiveness doesn't really matter here too much but it feels somewhat inconsistent

Instead, this happened: error

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[Jules-Bertholet]

#![feature(array_repeat)] is for #126695.

@rustbot label -F-array_repeat