QFuture should support move-only types

#include <QtConcurrent>
#include <memory>

static std::unique_ptr<int> allocateInt() { return std::make_unique<int>(); }

int main()
{
    const auto future = QtConcurrent::run(&allocateInt);
    return *future.result();
}

In file included from /usr/include/qt/QtCore/QtCore:91,
                 from /usr/include/qt/QtConcurrent/QtConcurrentDepends:3,
                 from /usr/include/qt/QtConcurrent/QtConcurrent:3,
                 from /tmp/untitled2/main.cxx:1:
/usr/include/qt/QtCore/qfuture.h: In instantiation of ‘T QFuture<T>::result() const [with T = std::unique_ptr<int>]’:
/tmp/untitled2/main.cxx:9:27:   required from here
/usr/include/qt/QtCore/qfuture.h:209:31: error: use of deleted function ‘std::unique_ptr<_Tp, _Dp>::unique_ptr(const std::unique_ptr<_Tp, _Dp>&) [with _Tp = int; _Dp = std::default_delete<int>]’
  209 |     return d.resultReference(0);
      |                               ^

#include <future>
#include <memory>

static std::unique_ptr<int> allocateInt() { return std::make_unique<int>(); }

int main()
{
  auto handle = std::async(std::launch::async, allocateInt);
  return *handle.get();
}