title: mainform.ui.qml is missing in new QtQuick project
body: <p>I'm pretty new in QT an have read/watched a lot of tutorials especially the QT documentation. Right now I'm stuck in creating new QTQuick projects.
  I have installed QT 6.2 and using a windows (Win 10) computer.
  Where ever I look I'm told, that QTCreator creates a file called mainform.ui.qml (when the concerning checkbox is checked) when setting up a new QtQuick project. In my case there isn't even a checkbox and after creating the project no mainform.ui.qml.
  As far as I understood the tutorials there is no special adjustment to be done to generate this file.</p>
  <p>Could anybody please give me a hint what to do to get this ui file generated automatically when creating a QTQuick application with QTCreator?</p>
  <p>Thanks a lot in advance for taking care of my question.</p>
  <p>Best regards from Bremen Germany</p>