remove unnecessary code
- remove `CacheEntryDoesNotExistError` and use `CachedArtifactNotFoundError` instead
- remove useless `get_response_or_missing_error`

remove unnecessary code: - remove `CacheEntryDoesNotExistError` and use `CachedArtifactNotFoundError` instead
- remove useless `get_response_or_missing_error`
