feat: implement concrete PyDotDAGBuilder subclass

[andrijapau]

This PR implements a concrete subclass for the PyDot backend.

[sc-103457]

[github-actions]

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Please edit doc/releases/changelog-dev.md with:

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.43%. Comparing base (5810cde) to head (db746e5).

Additional details and impacted files

@@                     Coverage Diff                      @@
##           feature/graph-visualization    #8630   +/-   ##
============================================================
  Coverage                        99.42%   99.43%           
============================================================
  Files                              587      587           
  Lines                            61967    61967           
============================================================
+ Hits                             61611    61614    +3     
+ Misses                             356      353    -3     

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