Improved tf_prefix based on namespace (backport #1420)

[mergify]

Fix test related with: #1060

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This is an automatic backport of pull request #1420 done by Mergify.

[codecov]

Codecov Report

Attention: Patch coverage is 71.42857% with 2 lines in your changes missing coverage. Please review.

Project coverage is 66.72%. Comparing base (b9816b5) to head (4f8730c).
Report is 1 commits behind head on humble.

Files with missing lines	Patch %	Lines
...ive_controller/test/test_diff_drive_controller.cpp	33.33%	0 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           humble    #1421      +/-   ##
==========================================
- Coverage   66.73%   66.72%   -0.01%     
==========================================
  Files         113      113              
  Lines       13214    13216       +2     
  Branches     8150     8152       +2     
==========================================
+ Hits         8818     8819       +1     
  Misses       1442     1442              
- Partials     2954     2955       +1     

Flag	Coverage Δ
unittests	66.72% <71.42%> (-0.01%)	⬇️

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

Files with missing lines	Coverage Δ
...iff_drive_controller/src/diff_drive_controller.cpp	73.15% <100.00%> (+0.09%)	⬆️
...ive_controller/test/test_diff_drive_controller.cpp	63.87% <33.33%> (+0.13%)	⬆️

... and 3 files with indirect coverage changes