get https://api.codecov.io/api/v2///repos//compare/impacted_files
Returns a comparison for either a pair of commits or a pull
Will only return pre-computed impacted files comparisons if available
If unavailable files will be empty, however once the computation is ready
the files will appear on subsequent calls
state: "processed" means files are finished computing and returned
state: "pending" means files are still computing, poll again later