Use new Joint APIs for Parent/Child name

[scpeters]

🦟 Bug fix

Follow-up to gazebosim/sdformat#1053.

Summary

Checklist

• Signed all commits for DCO
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• While waiting for a review on your PR, please help review another open pull request to support the maintainers

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by messages.

[codecov]

Codecov Report

Merging #361 (433a4d6) into main (a950315) will not change coverage.
The diff coverage is 43.75%.

@@           Coverage Diff           @@
##             main     #361   +/-   ##
=======================================
  Coverage   74.55%   74.55%           
=======================================
  Files         128      128           
  Lines        5628     5628           
=======================================
  Hits         4196     4196           
  Misses       1432     1432           

Impacted Files	Coverage Δ
dartsim/src/SDFFeatures.cc	62.71% <35.71%> (ø)
bullet/src/SDFFeatures.cc	45.06% <100.00%> (ø)

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