qt: fix handling BIP21 URI from e.g. website on macOS

fixes #6933

based on e2171f702d

Co-authored-by: SomberNight <somber.night@protonmail.com>

electrum/gui/qt/__init__.py

@@ -73,7 +73,7 @@ class OpenFileEventFilter(QObject):
     def eventFilter(self, obj, event):
         if event.type() == QtCore.QEvent.FileOpen:
             if len(self.windows) >= 1:
-                self.windows[0].pay_to_URI(event.url().toEncoded())
+                self.windows[0].pay_to_URI(event.url().toString())
                 return True
         return False