Don't trigger third-party printer dialog when onCloudPrintersDetected changed

That signal is received basically every minute when you're already signed in
and it will close the dialog when no new cloud printers are found.

Contributes to CURA-8689

resources/qml/WelcomePages/AddUltimakerPrinter.qml

@@ -22,10 +22,6 @@ Control
         {
             base.goToPage("add_cloud_printers")
         }
-        else
-        {
-            goToThirdPartyPrinter()
-        }
     }
 
     contentItem: ColumnLayout