Introducing e2e slurm tests

[asmacdo]

This PR introduces a full e2e test that loosely corresponds with the example walkthrough

To do this, we use a SLURM "microcluster" run inside a container.

TODO:

• : Build a new docker-centos7-slurm image upstream and switch back to it
  • Build and push new container image on merge giovtorres/docker-centos7-slurm#54
• : Switch back to the osf dataset provided in the walkthrough (or remove TODO, seems fine as is, and doesnt need osf cred)

[asmacdo]

Not sure why the new tests didn't run here, they did run on my fork

https://github.com/asmacdo/babs/actions/runs/7670941389/job/20908224578

[yarikoptic]

may be because it is a new workflow and there are some secrets so github isn't running it by default for external contributors? but overall -- dunno.