Fix unnecessary-return-none in telnet (#122949)

homeassistant/components/telnet/switch.py

@@ -144,7 +144,7 @@ class TelnetSwitch(SwitchEntity):
             rendered = self._value_template.render_with_possible_json_value(response)
         else:
             _LOGGER.warning("Empty response for command: %s", self._command_state)
-            return None
+            return
         self._attr_is_on = rendered == "True"
 
     def turn_on(self, **kwargs: Any) -> None: