Updates to error handling.

Added question to error handler. Added get_question method to get the current question from the request object. Initiate a rollback for all exceptions, since we don't know what has succeeded/failed, and we could be in a bad state.

What's New?

This refactors the way we extract a question from a request into a function, with a BadRequest being raised when we are not able to extract the question.

Fixes #197 (partially). We should also retry questions that fail, but that's not in this PR.

Type of change (pick-one)

[x] Bug fix (non-breaking change which fixes an issue)
[ ] New feature (non-breaking change which adds functionality)
[ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
[ ] This change requires a documentation update

How Has This Been Tested?

Killed network connection to mysql to cause broken sessions. These were cleaned up correctly after reconnecting to the internet.

Checklist (check-all-before-merge)

formatting help: - [x] means "checked' and - [ ] means "unchecked"

[ ] I documented my code according to the Google Python Style Guide
[ ] I ran ./build_docs.sh and the docs look fine
[ ] I ran ./type_check.sh and got no errors
[ ] I ran ./format.sh because it automatically cleans my code for me 😄
[ ] I ran ./lint.sh to check for what "format" missed
[ ] I added my tests to the /tests directory
[x] I ran ./run_tests.sh and all the tests pass

calpoly-csai / api