Add integration tests with database connection

Currently, tests are mocking every database connection or are skipped (`pytest.mark.skip` in `test_geodatabase.py`).
In order to cleanup database-access-related code (especially avoid having 2 different persistence libraries),
the geo-database tests have to be reactivated first.

Tasks:

* reactivate existing geo-database tests
* consider using the `PostGIS` module of `test containers`
* find an appropriate subset for populating the test database
* try running the Jenkins build outside docker in order to avoid problems with `test containers `

Blocks https://github.com/GIScience/ohsome-quality-api/issues/746