qt: factor out remaining ChoicesLayout uses

electrum/plugins/digitalbitbox/qt.py

@@ -69,6 +69,10 @@ class DigitalBitbox_Handler(QtHandlerBase):
     def __init__(self, win):
         super(DigitalBitbox_Handler, self).__init__(win, 'Digital Bitbox')
 
+    def query_choice(self, msg, labels):
+        choices = [(i, v) for i, v in enumerate(labels)]
+        return QtHandlerBase.query_choice(self, msg, choices)
+
 
 class WCDigitalBitboxScriptAndDerivation(WCScriptAndDerivation):
     requestRecheck = pyqtSignal()