Setup test suite with GH actions

[HendrikStrobelt]

Make sure all tests work on supported Python versions: 3.10, 3.11,... < 4.0

[nrfulton]

FYI, I think @avinash2692 was already working on GH actions for tests and releases. Just want to make sure we're not duplicating work...

[jakelorocco]

Sounds good. yes, I hadn't started here, it's just been coming up in our discussions with docling quite a bit.