refs https://github.com/TryGhost/Toolbox/issues/120
- When editing an uploaded media thumbnail file there'a need to remove existing thumbnail to keep media files:thumbnails 1:1. - Because the API client only has a public URL under which the resource is served it can only provide that as an API input, the `urlToPath` was also added to the base class of LocalStorageAdapter (it might be moved up to the BaseAdapter in the future if we see a need)
refs https://linear.app/tryghost/issue/CORE-1/multiple-adapters-per-type
- While digging around this area refactored the code to use more readable async/await syntax instead of chaining then's
- Dropped unneeded "catch" block in save method as all it was doing was rethrowing an error with out additional handling
- this is a small part of a bit of cleanup of our test files
- the goal is to make the existing tests clearer with a view to making it easier to write more tests
- this makes the test structure follow the codebase structure more closely
- eventually we will colocate the tests as we break the codebase down further
