Enabling soft realtime prioritization to the Controller Server (backport #3914)

[mergify]

This is an automatic backport of pull request #3914 done by Mergify.
Cherry-pick of fbe8f56 has failed:

On branch mergify/bp/humble/pr-3914
Your branch is up to date with 'origin/humble'.

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  (fix conflicts and run "git cherry-pick --continue")
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Changes to be committed:
	modified:   nav2_bringup/params/nav2_params.yaml
	modified:   nav2_controller/include/nav2_controller/controller_server.hpp
	modified:   nav2_util/include/nav2_util/node_thread.hpp
	modified:   nav2_util/include/nav2_util/simple_action_server.hpp
	modified:   nav2_util/src/node_thread.cpp

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   nav2_controller/src/controller_server.cpp

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

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[mergify]

@mergify[bot], all pull requests must be targeted towards the main development branch.
Once merged into main, it is possible to backport to @humble, but it must be in main
to have these changes reflected into new distributions.