Afero is a package that lets you mock out a filesystem with an in-memory filesystem.
It allows us to easily create the files required for a given test without worrying about
a cleanup step or different tests tripping on eachother when run in parallel.
Later on I'll standardise on using afero over the vanilla os package
Now that we run code concurrently in our loaders, we need to handle that in our tests.
We could enforce a deterministic ordering by mocking waitgroup or something like that,
but I think it's fine to let our tests handle some randomness given that prod itself
will have that randomness.
I've removed the patch test file because it was clunky, not providing much value, and
it would have been hard to refactor to the new pattern
