Replace std::decay with std::remove_cvref after C++20

[AlCash07]

C++20 will have a new trait std::remove_cvref that doesn't have undesirable effect of std::decay on arrays, so maybe it's worth using it for example here: https://github.com/thecppzoo/zoo/blob/d59092ae807a6a8780981dcd0dfb8104ea8ba81d/inc/meta/NotBasedOn.h#L14