Can't enable cache on local board

[wklimowicz]

First off, thanks for your work on this package!

I'm in the same situation as #669, where I want to enable caching for a slow network drive. The two functions suggested in #669 create a board, and create a folder inside ~/.cache/pins/, but the cache doesn't populate with any files. I've created a reprex repo here with a GitHub action showing that no file get's created after pin_read. Am I misunderstanding when the caching is intended to happen?

https://github.com/wklimowicz/pins-bug-no-cache/