Port from qAsConst() to std::as_const()

We've been requiring C++17 since Qt 6.0, and our qAsConst use finally
starts to bother us (QTBUG-99313), so time to port away from it
now.

Since qAsConst has exactly the same semantics as std::as_const (down
to rvalue treatment, constexpr'ness and noexcept'ness), there's really
nothing more to it than a global search-and-replace.

Task-number: QTBUG-99313
Change-Id: I88edd91395849574436299b8badda21bb93bea39
Reviewed-by: hjk <hjk@qt.io>

src/plugins/macros/macrooptionswidget.cpp

@@ -135,7 +135,7 @@ void MacroOptionsWidget::remove()
 void MacroOptionsWidget::apply()
 {
     // Remove macro
-    for (const QString &name : qAsConst(m_macroToRemove)) {
+    for (const QString &name : std::as_const(m_macroToRemove)) {
         MacroManager::instance()->deleteMacro(name);
         m_macroToChange.remove(name);
     }