Constant timeout in RosServiceNode

[fmros]

I stumbled over a use-case where a service call is taking longer than 1 second. I do not want to globally increase the service timeout over the BT::RosNodeParams parameter as this would affect all plugins I am using.

Is there any concern about removing the const declaration of service_timeout_ variable for the ROS2 service timeout here? This way one could overwrite the value in the setRequest() function (and get the timeout value eventually over an input port).

Let me know and i will file a PR.