Check alternative connections when connecting
QNetworkAccessManager keeps track of a single connected session (e.g. Wifi, mobile data) at a time. If the currently tracked session disconnects, it checks whether any other network configuration is online, and if so, it switches to make this the current session.
However, if the currently tracked session changes to the Connecting state, QNetworkAccessManager will move into the offline state, and further changes to the connectivity of the tracked session will no longer trigger an update.
This change makes QNetworkAccessManager switch connection in case the current session moves to the Connecting state while another Active online configuration is available to use instead.