Feature/6360 add statement timeout

[cnlucas]

Summary (required)

• Resolves Consider adding statement_timeout to engine config #6360

Add statement timeout for RO sessions

Required reviewers

2-3 devs

Impacted areas of the application

General components of the application that this PR will affect:

• sqlalchemy sessions timeout

How to test

• pull this PR

• pytest

• set an artificially low statement timeout locally
  export SQLA_STATEMENT_TIMEOUT=1

• flask run

• Run any query and you should see a 408 error, you can try a 404 and 422 as well:
  408: http://127.0.0.1:5000/v1/committees/?page=1&per_page=20&filing_frequency=M&sort=name&sort_hide_null=false&sort_null_only=false&sort_nulls_last=false
  404: http://127.0.0.1:5000/v1/committes/?page=1&per_page=20&filing_frequency=M&sort=name&sort_hide_null=false&sort_null_only=false&sort_nulls_last=false
  422: http://127.0.0.1:5000/v1/committees/?page=1&per_page=20&filing_frequency=ZZ&sort=name&sort_hide_null=false&sort_null_only=false&sort_nulls_last=false