Fix retaining the correct folders on macOS too

BenchmarkDemoQt6/remotecontrolsender.cpp

@@ -245,10 +245,12 @@ const QString RemoteControlSender::save(const QString &filename)
 
 void RemoteControlSender::selectTestScriptFile()
 {
-    QUrl scriptfile = QFileDialog::getOpenFileUrl(nullptr,
-                                                  QLatin1String("Select Script File"),
-                                                  m_testSetFile,
-                                                  QLatin1String("Script Files (*.json)"));
+    QFileDialog dialog;
+    dialog.setDirectory(m_testSetFile);
+    QUrl scriptfile = dialog.getOpenFileUrl(nullptr,
+                                            QLatin1String("Select Script File"),
+                                            {},
+                                            QLatin1String("Script Files (*.json)"));
     if (!scriptfile.isEmpty()) {
         m_testSetFile = scriptfile.toLocalFile();
         emit testSetFileChanged();