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/debugger/breakhandler.cpp

@@ -2035,7 +2035,7 @@ void BreakHandler::releaseAllBreakpoints()
     }
     clear();
     // Make now-unclaimed breakpoints globally visible again.
-    for (GlobalBreakpoint gbp: qAsConst(gbps)) {
+    for (GlobalBreakpoint gbp: std::as_const(gbps)) {
         if (gbp)
             gbp->updateMarker();
     }