Infrom user why rt policy could not be set, infrom if is set. (backport #1705)

[mergify]

Print out information why setting of rt policy could not be set. Additionally inform if successfully set the rt policy

---

This is an automatic backport of pull request #1705 done by Mergify.

[mergify]

Cherry-pick of dd352eb has failed:

On branch mergify/bp/humble/pr-1705
Your branch is up to date with 'origin/humble'.

You are currently cherry-picking commit dd352eb.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   controller_manager/src/ros2_control_node.cpp

no changes added to commit (use "git add" and/or "git commit -a")

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

[christophfroehlich]

Failed because of missing backport of #1142

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.

Project coverage is 62.30%. Comparing base (19c52a6) to head (289b98f).
Report is 1 commits behind head on humble.

Files	Patch %	Lines
controller_manager/src/ros2_control_node.cpp	0.00%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           humble    #1708   +/-   ##
=======================================
  Coverage   62.30%   62.30%           
=======================================
  Files         105      105           
  Lines       11314    11314           
  Branches     7925     7928    +3     
=======================================
  Hits         7049     7049           
  Misses        806      806           
  Partials     3459     3459           

Flag	Coverage Δ
unittests	62.30% <0.00%> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
controller_manager/src/ros2_control_node.cpp	80.00% <0.00%> (ø)