[libcxx][test] {move,reverse}_iterator cannot be instantiated for a type with no `operator*`

Since their nested reference types are defined in terms of `iter_reference_t<T>`, which examines `decltype(*declval<T>())`.

Differential Revision: https://reviews.llvm.org/D117371

NOKEYCHECK=True
GitOrigin-RevId: cfe17986c952e552a731237da99f4879def3a02b
3 files changed