qt: Do not exit and re-enter main event loop during shutdown

src/qt/optionsdialog.cpp

@@ -290,7 +290,8 @@ void OptionsDialog::on_resetButton_clicked()
 
         /* reset all options and close GUI */
         model->Reset();
-        QApplication::quit();
+        close();
+        Q_EMIT quitOnReset();
     }
 }