Move question answer logic into Session.answer_question()

[dhalperi]

QuestionBase.answer() previously called _bf_answer_obj(), a free function in internal.py that directly invoked restv2helper and workhelper, bypassing the session. This made it impossible for Session subclasses to override question answering behavior.

Move that logic into Session.answer_question() and have QuestionBase.answer() call it via self._session. Remove the now-unused _bf_answer_obj() function.

---

Prompt:

Make session.q(params).answer() call back into session so that
subclasses can override the question answer transport.

commit-id:fa22b8a7

[batfish-bot]

This change is 

[dhalperi]

@dhalperi reviewed 3 files and all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on dhalperi).

[codecov]

Codecov Report

❌ Patch coverage is 84.61538% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 87.79%. Comparing base (4bce0e1) to head (a0c1398).

Files with missing lines	Patch %	Lines
pybatfish/client/session.py	77.77%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #975      +/-   ##
==========================================
- Coverage   87.80%   87.79%   -0.02%     
==========================================
  Files          26       26              
  Lines        3773     3769       -4     
  Branches      503      503              
==========================================
- Hits         3313     3309       -4     
  Misses        330      330              
  Partials      130      130              

Files with missing lines	Coverage Δ
pybatfish/client/internal.py	100.00% <100.00%> (+11.11%)	⬆️
pybatfish/question/question.py	81.37% <100.00%> (ø)
pybatfish/client/session.py	81.28% <77.77%> (-0.10%)	⬇️

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[dhalperi]

@dhalperi reviewed 1 file and all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on dhalperi).