feat: Add ros2_control doxygen documentation support

[jaron-l]

• Add GitHub workflow step to checkout ros2_control
• Add breathe settings to conf.py

This is in reference to ros2_control #332

[bmagyar]

Yes guys please fix it in whatever way we can :D I personally prefer the deployment script as that allows (or at least used to) local testing and keeps all the deployment logic in one place. However I had no time for fixing it and not likely I will have in the near future.

[jaron-l]

@destogl and @bmagyar, my recent commits show the fully converted workflows to GitHub actions. I added documentation on how you can locally test the workflows to the README.md to address @bmagyar's concern. I still think this way is easier as it requires less code maintenance from us for any future changes (though that does require using an external package to make it really easy). Let me know what you think.

[bmagyar]

Thanks very much for the effort, especially for the readme ;)