Avoid using port 0 for SpotCamWrapper (#124)

Signed-off-by: Michel Hidalgo <[email protected]>

spot_wrapper/cam_wrapper.py

@@ -915,7 +915,7 @@ def __init__(
         spot_cam.register_all_service_clients(self.sdk)
 
         self.robot = self.sdk.create_robot(self._hostname)
-        if port is not None:
+        if port:
             self.robot.update_secure_channel_port(port)
         SpotWrapper.authenticate(self.robot, self._username, self._password, self._logger)