Address DB errors in `make test`

[michplunkett]

What issue are you seeing?

These errors are coming up during testing:

../../local/lib/python3.11/site-packages/flask_wtf/recaptcha/widgets.py:2: 10 warnings
  /usr/local/lib/python3.11/site-packages/flask_wtf/recaptcha/widgets.py:2: DeprecationWarning: 'flask.Markup' is deprecated and will be removed in Flask 2.4. Import 'markupsafe.Markup' instead.
    from flask import Markup

OpenOversight/tests/test_database_cache.py::test_get_database_cache_entry
OpenOversight/tests/test_commands.py::test_add_department__success
OpenOversight/tests/test_email_client.py::test_smtp_email_provider_send_email
OpenOversight/tests/test_alembic.py::test_alembic_has_single_head
  /usr/src/app/OpenOversight/tests/conftest.py:649: RemovedIn20Warning: Deprecated API features detected! These feature(s) are not compatible with SQLAlchemy 2.0. To prevent incompatible upgrades prior to updating applications, ensure requirements files are pinned to "sqlalchemy<2.0". Set environment variable SQLALCHEMY_WARN_20=1 to show all deprecation warnings.  Set environment variable SQLALCHEMY_SILENCE_UBER_WARNING=1 to silence this message. (Background on SQLAlchemy 2.0 at: https://sqlalche.me/e/b8d9)
    Incident(

OpenOversight/tests/test_commands.py::test_add_department__duplicate
OpenOversight/tests/test_models.py::test__uuid_uniqueness_constraint
OpenOversight/tests/routes/test_singular_redirects.py::test_redirect_add_salary
  /usr/src/app/OpenOversight/tests/conftest.py:327: SAWarning: transaction already deassociated from connection
    transaction.rollback()

OpenOversight/tests/test_models.py::test_salary_repr
  /usr/src/app/OpenOversight/tests/test_models.py:170: SAWarning: Dialect sqlite+pysqlite does *not* support Decimal objects natively, and SQLAlchemy must convert from floating point - rounding errors and other issues may occur. Please consider storing Decimal numbers as strings or integers on this platform for lossless storage.
    salary = Salary.query.first()

OpenOversight/tests/test_database_cache.py::test_documented_assignments
  /usr/local/lib/python3.11/site-packages/jinja2/environment.py:485: SAWarning: Dialect sqlite+pysqlite does *not* support Decimal objects natively, and SQLAlchemy must convert from floating point - rounding errors and other issues may occur. Please consider storing Decimal numbers as strings or integers on this platform for lossless storage.
    return getattr(obj, attribute)

OpenOversight/tests/test_commands.py::test_csv_import_new
  /usr/src/app/OpenOversight/tests/conftest.py:829: SAWarning: Dialect sqlite+pysqlite does *not* support Decimal objects natively, and SQLAlchemy must convert from floating point - rounding errors and other issues may occur. Please consider storing Decimal numbers as strings or integers on this platform for lossless storage.
    if len(list(officer.salaries)) > 0:

OpenOversight/tests/test_commands.py::test_csv_new_salary
  /usr/src/app/OpenOversight/tests/test_commands.py:463: FutureWarning: Setting an item of incompatible dtype is deprecated and will raise in a future error of pandas. Value '123456.78' has dtype incompatible with float64, please explicitly cast to a compatible dtype first.
    df.loc[0, "salary"] = "123456.78"