Support setting parameters atomically using ros2 service command line #721

Feature request

It would be nice to support setting params atomically using ros2 service call command line.

Feature description

Currently, the ros2 service call sets parameters in a non atomic fashion, meaning if one fails it wouldn't affect the other params being set. It would good to support an optional argument --atomically or something which could help in debugging and testing if params are required to be set in an atomic fashion using the command line.

Implementation considerations

For setting the params atomically using ros2 service call we could leverage the already existing Node API service rcl_interfaces::srv::SetParametersAtomically.