CI/CD and testing

[rvosa]

The current CI/CD pipeline is limited to some very basic checks. It would be better if this was extended to do tests, but the precise scope is to be determined. Some considerations:

• Apparently, the output of a SnakeMake pipeline can somehow be adapted to a test suite. On small test data this may be good to explore.
• The code is now largely independent scripts, with some minimal delegation to shared modules. There may be some scope for factoring out more functionality to a reusable modules, which may be unit tested.
• As different, increasingly larger cases are attempted, the code continues to be modified. It would be good if regressions were tested.