Add tests

[proofconstruction]

Add tests

[kwcckw]

Yea, i do agree we need a proper test script but with the rapid development and changes from the current repo, if we add in a test script now, it might become obsolete again very soon. Unless the test script is general enough to allow tests with some major changes, and it would be good if it is capable to detect runtime error and static error too.

[jboarman]

I suggest a very simple start on this. Eventually we should make the tests run using GitHub Actions, but getting a very small and basic set of tests will be a huge step in and of itself. Integrating these as a required step triggered as part of the PR process may be a slightly less frustrating process than using pre-commit hooks to run tests.

[proofconstruction]

GH Action to lint and run a simple pytest was added with this commit.