add various integration tests

[malmans2]

• Add some integration tests for features such as area selection and format conversion.
• Add some integration tests for testing real datasets. We should not rely on real datasets for these integration tests, as they are affected by external factors such as forms configuration. We are implementing these tests in this repository as a temporary solution, and they will be moved to a dedicated repository. Therefore, all integration tests using real datasets are executed using xfail.