Working async controllers and components [not synchronized] (backport #1041)

[mergify]

I haven't found a good way to synchronize the controllers / components with the ros2 control node's thread without changing a lot of stuff inside the handles (and controllers), and since they are getting reworked anyway, I thought I'll wait until then.

Before that, this solution assumes that all writes to the command interfaces' double values are atomic operations.

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This is an automatic backport of pull request #1041 done by Mergify.

[mergify]

Cherry-pick of 2cbe470 has failed:

On branch mergify/bp/humble/pr-1041
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Changes to be committed:
	new file:   controller_interface/include/controller_interface/async_controller.hpp
	modified:   controller_manager/src/ros2_control_node.cpp
	modified:   hardware_interface/include/hardware_interface/resource_manager.hpp

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	both modified:   controller_manager/include/controller_manager/controller_manager.hpp
	both modified:   controller_manager/src/controller_manager.cpp
	deleted by us:   hardware_interface/include/hardware_interface/async_components.hpp
	both modified:   hardware_interface/src/resource_manager.cpp

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally