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/designer/settingspage.cpp

@@ -96,7 +96,7 @@ bool SettingsPageProvider::matches(const QRegularExpression &regex) const
         for (size_t i = 0; i < itemCount; ++i)
             m_keywords << Utils::stripAccelerator(QCoreApplication::translate(uitext[i].context, uitext[i].value));
     }
-    for (const QString &key : qAsConst(m_keywords)) {
+    for (const QString &key : std::as_const(m_keywords)) {
         if (key.contains(regex))
             return true;
     }