ci: add Python 3.13 to workflows and packaging metadata
This PR updates CI workflows and packaging metadata so we can test the adapter on Python 3.13.
Depends on: #623 Adapter migration PR (adapter code changes required for Fabric 1.9.6): #5 — merge adapter changes before enabling full integration test coverage on 3.13.
#624 ci/docker-images-3.13 (this PR depends on the Docker images PR which must be merged first so the integration jobs can reference published CI images)
Summary
Previous PR Changes Add Python 3.13 to the unit test matrix (.github/workflows/unit-tests.yml). Add Python 3.13 to the integration test matrix (.github/workflows/integration-tests-sqlserver.yml). Add Python 3.13 classifier to packaging metadata (setup.py).
Why
Fabric 1.9.6 and platform updates make adding Python 3.13 desirable. We must first publish 3.13 CI images so integration tests can run against images that include the necessary binary deps (ODBC driver, pyodbc wheels, etc.).