Fix child_frame_id in controller_state_msg (backport #1601)

[mergify]

Closing #504

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This is an automatic backport of pull request #1601 done by [Mergify](https://mergify.com).

[codecov]

Codecov Report

Attention: Patch coverage is 63.15789% with 7 lines in your changes missing coverage. Please review.

Project coverage is 67.09%. Comparing base (b0569b2) to head (05807d1).
Report is 1 commits behind head on humble.

Files with missing lines	Patch %	Lines
...nce_controller/test/test_admittance_controller.cpp	53.33%	0 Missing and 7 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           humble    #1834      +/-   ##
==========================================
- Coverage   67.10%   67.09%   -0.02%     
==========================================
  Files         122      122              
  Lines       14531    14546      +15     
  Branches     8970     8986      +16     
==========================================
+ Hits         9751     9759       +8     
- Misses       1455     1461       +6     
- Partials     3325     3326       +1     

Flag	Coverage Δ
unittests	67.09% <63.15%> (-0.02%)	⬇️

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

Files with missing lines	Coverage Δ
...ude/admittance_controller/admittance_rule_impl.hpp	92.51% <100.00%> (ø)
...nce_controller/test/test_admittance_controller.hpp	93.26% <ø> (ø)
...nce_controller/test/test_admittance_controller.cpp	54.33% <53.33%> (-0.10%)	⬇️

... and 1 file with indirect coverage changes

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