Fix invalid PropertyDelegate::createEditor
Fix invalid PropertyDelegate::createEditor

According to the documentation[^1] createEditor should return a QWidget
with a focus of Qt::StrongFocus or Qt::WheelFocus.

[^1]: https://doc.qt.io/qt-5/qabstractitemdelegate.html#createEditor

undisbeliever/untech-editor,undisbeliever/untech-editor