kded: Ignore GetReady() signal from system-config-printer
** This applies to USB connected printers ONLY **
System-config-printer (SCP) package notifies on the system bus of a new connected printer with GetReady() and shortly after, gives another signal, NewPrinter() with the status of config of the newly connected printer. We listen for both and pop a notification for each. Since 6.5?, Plasma now also notifies of a new device connected (USB), so reacting to GetReady() is redundant, though, it asks device manager to dismiss it's notification so only one "device connected" notification should show.
This MR:
Instead, let's just depend on the plasma device notification (it's more detailed) and remove the notification option for the GetReady() signal from SCP. In addition, if/when we receive the NewPrinter() signal from SCP, have it dismiss the device notification as well.
This is the first step in reducing reliance on the SCP package.
Testing:
Connect a USB printer to your computer