Try using cabal-cache for github CI

Here's the link:

https://hackage.haskell.org/package/cabal-cache

We could stop caching store/ and instead cache something safer, more selective and not causing our test to fail due to the dreaded

```
Error: Ambiguous module name ‘System.Directory’:
it was found in multiple packages:
directory-1.3.7.1 directory-1.3.7.1
```