Disable dialogs to allow changes in qtbase (use urls internally)

Followup to I9ae09416acdbe437acbe9672d0ecfc42059695ae so qtbase change
I61e99d498252241f38ec05724702a90ba050c4bb can get through CI.

Change-Id: I8bf3bca9b2a3b00b2471045cdc73f20329f99d9d
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>