Comparison traits should check for boolean return type

[deadlocklogic]

Currently the comparison traits are using:
supports_op_less_test -> void_t<decltype(std::declval<T&>() < std::declval<U&>())>
supports_op_equal_test -> void_t<decltype(std::declval<T&>() == std::declval<U&>())>
supports_op_less_equal_test -> void_t<decltype(std::declval<T&>() <= std::declval<U&>())>
instead of:
std::enable_if_t<std::is_same_v<decltype(std::declval<T&>() < std::declval<U&>()), bool>>
std::enable_if_t<std::is_same_v<decltype(std::declval<T&>() == std::declval<U&>()), bool>>
std::enable_if_t<std::is_same_v<decltype(std::declval<T&>() <= std::declval<U&>()), bool>>
Because some libraries have their weird own comparison return type, especially with optional types.