[JTC] Add new test to ensure that controller goes into position holding when tolerances are violated 

[...] Would it be possible to write a small test for this behavior? We would then feel better in the future to know that behavior is not broken (again).

_Originally posted by @destogl in https://github.com/ros-controls/ros2_controllers/pull/368#pullrequestreview-1019716551_