Added Box python interface

[ahcorde]

Signed-off-by: ahcorde ahcorde@gmail.com

🎉 New feature

This PR is part of this mete ticket #931

Summary

Added Box Python interface

Test it

from sdformat import Box

box = Box()

Checklist

• Signed all commits for DCO
• Added tests
• Added example and/or tutorial
• Updated documentation (as needed)
• Updated migration guide (as needed)
• 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-commenter]

Codecov Report

Merging #937 (aeb9f3b) into main (96ab662) will decrease coverage by 0.01%.
The diff coverage is 68.42%.

❗ Current head aeb9f3b differs from pull request most recent head ece62d7. Consider uploading reports for the commit ece62d7 to get more accurate results

@@            Coverage Diff             @@
##             main     #937      +/-   ##
==========================================
- Coverage   88.07%   88.06%   -0.02%     
==========================================
  Files         103      104       +1     
  Lines       14744    14765      +21     
==========================================
+ Hits        12986    13003      +17     
- Misses       1758     1762       +4     

Impacted Files	Coverage Δ
python/src/sdf/pyBox.cc	66.66% <66.66%> (ø)
python/src/sdf/_ignition_sdformat_pybind11.cc	100.00% <100.00%> (ø)
src/Box.cc	97.22% <0.00%> (+5.55%)	⬆️

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[azeey]

Just one minor comment about the test.