Correctly call self.close() in disconnected_callback for bleak (fixes #770)

meshtastic/ble_interface.py

@@ -174,7 +174,7 @@ class BLEInterface(MeshInterface):
 
         # Bleak docs recommend always doing a scan before connecting (even if we know addr)
         device = self.find_device(address)
-        client = BLEClient(device.address, disconnected_callback=lambda _: self.close)
+        client = BLEClient(device.address, disconnected_callback=lambda _: self.close())
         client.connect()
         client.discover()
         return client