Explore options to store hdf5 files used by pytest externally

[DaniBodor]

Currently, each time we change something about the features, there is a potential that the tests break because the files in tests/hdf5/ are no longer representative. At this point we need to recreate the hdf5 files. Each time we do this, we add ~50MB (?) in "dead weight" to the repo (all the old files will be part of the .git folder).

We should check for other options to store the test data external to this repo (or some other option), so that cloning it doesn't carry all the dead weight.

We should talk to @Cunliang about how he did this for NPLinker.

[github-actions[bot]]

This issue is stale because it has been open for 30 days with no activity.