Use Generic Steering Controller State Message in Steering Controllers Library

[mbharatheesha]

I was reading through the code as a part of learning how to write a new steering controller. I understood that a new steering controller inherits from the SteeringControllersLibrary. But I also found the use of Ackermannxxx in the base class code for a status message and the same was being used in other steering controllers such as BicycleSteeringController and TricycleSteeringController.

If I understood the inheritance and the code structure correctly, the SteerinControllersLibrary should be agnostic to the specifics of a steering controller that derives from it. Therefore, this PR introduces the following changes:

• Remove the use of Ackermannxxx declarations in the SteeringControllersLibrary base class and rename it to SteeringControllerStateMsg
• Modify the tests and state publishers to use the renamed declaration
• Remove ackermann_msgs dependency from steering_controllers_library package.

All tests for the modified packages were run successfully (locally).

[christophfroehlich]

LGTM, thanks for the cleanup.

According to our guidelines: Please target the PR to the master branch, and we will perform backports to iron+humble.

[bmagyar]

For humble and iron we can only deprecate the use of these messages. Full removal can be done on rolling

[christophfroehlich]

but it doesn't change anything for users, only inherited classes may be broken. we could maybe use the [[deprecated]] c++ qualifier if necessary.

[mbharatheesha]

Apologies for the late response. Thanks for your remarks. I will submit a new PR targeted at master later today.

[mbharatheesha]

Closing this in favor of #836.