Mark Qt Positioning as a dependency of Qt WebEngine

Issue

On a Desktop platform (tested on Windows), if you install Qt WebView and Qt WebEngine but not Qt Positioning, the Minibrowser example (https://doc.qt.io/qt-6/qtwebview-minibrowser-example.html ) mysteriously fails to run.

Setting QT_DEBUG_PLUGINS=1 does not reveal anything obvious:

[22556] qt.core.plugin.loader: QLibraryPrivate::loadPlugin failed on "C:/Qt/Examples/Qt-6.3.0/webview/build-minibrowser-Desktop_Qt_6_3_0_MSVC2019_64bit-Release/release/webview/qtwebview_webengine.dll" : "Cannot load library C:\\Qt\\Examples\\Qt-6.3.0\\webview\\build-minibrowser-Desktop_Qt_6_3_0_MSVC2019_64bit-Release\\release\\webview\\qtwebview_webengine.dll: The specified module could not be found."

Suggestions

• The installer should auto-install Qt Positioning if Qt WebEngine is installed.
• (Similar but somewhat unrelated) The installer should auto-install Qt WebEngine if Qt WebView is installed on a Desktop platform.