Fix clang14 errors when compiling plasma-workspace
Clang14 is still the default clang version on KDE Neon. Also, clazy is build against it. Since it is not too much effort, we should try to be compatible for now.
The const auto pendingOutputs = std::views::values(std::as_const(orderMap)); !std::ranges::equal(pendingOutputs, std::as_const(m_outputOrder))
alternative is rather verbose. Since we also allocate a new list in that case, it used an ifdef for now.
See also libplasma!1185 (merged)