[JTC] Flaky CI test: test_state_publish_rate

[christophfroehlich]

I've seen that failing several times in different jobs.
https://github.com/ros-controls/ros2_controllers/actions/runs/8933149703/job/24538080159 or #1115

     /home/runner/work/ros2_controllers/ros2_controllers/.work/target_ws/src/ros2_controllers/joint_trajectory_controller/test/test_trajectory_controller.cpp:883
    The difference between target_msg_count and echo_received_counter is 2, which exceeds 1, where
    target_msg_count evaluates to 10,
    echo_received_counter evaluates to 8, and
    1 evaluates to 1.