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/git/gerrit/gerritmodel.cpp

@@ -908,7 +908,7 @@ void GerritModel::resultRetrieved(const QByteArray &output)
     std::stable_sort(changes.begin(), changes.end(), gerritChangeLessThan);
     numberIndexHash.clear();
 
-    for (const GerritChangePtr &c : qAsConst(changes)) {
+    for (const GerritChangePtr &c : std::as_const(changes)) {
         // Avoid duplicate entries for example in the (unlikely)
         // case people do self-reviews.
         if (!itemForNumber(c->number)) {