feat: ACTS reader
This PR introduces a first version of an ACTS reader. It is based on the TrackML reader and also uses its utility functions. I wrote some basic tests for it as well (could be probably improved).
Regarding the tests, I have also a small question: I needed to add sys.path.append("../gnn4itk_cf")
to make it work for me, however, the other tests only have sys.path.append("../")
. Is this a problem of my local setup?