Create QBluetoothServer unit test from QRfcommServer/QL2CAPServer tests

Task-number: QTBUG-22017
Change-Id: I3e5613153d2496567f7afd87c8a0a44c1067a4e7
Reviewed-by: Nedim Hadzic <nedimhadzija@gmail.com>
Reviewed-by: Alex Blasche <alexander.blasche@digia.com>