sweep: trivial clean-up

- wallet.get_receiving_addresses is guaranteed to exist (maybe it was only for HD wallets in the past)
- wallet.is_mine is stricter than wallet.adb.is_mine, usually we want the former

electrum/gui/qml/qetxfinalizer.py

@@ -901,7 +901,7 @@ class QETxSweepFinalizer(QETxFinalizer):
 
     def make_sweep_tx(self):
         address = self._wallet.wallet.get_receiving_address()
-        assert self._wallet.wallet.adb.is_mine(address)
+        assert self._wallet.wallet.is_mine(address)
 
         coins, keypairs = copy.deepcopy(self._txins)
         outputs = [PartialTxOutput.from_address_and_value(address, value='!')]

electrum/gui/qt/main_window.py

@@ -2387,10 +2387,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger, QtEventListener):
 
         addresses = self.wallet.get_unused_addresses()
         if not addresses:
-            try:
-                addresses = self.wallet.get_receiving_addresses()
-            except AttributeError:
-                addresses = self.wallet.get_addresses()
+            addresses = self.wallet.get_receiving_addresses()
         h, address_e = address_field(addresses)
         vbox.addLayout(h)