Serve an attachment file linked to a comment visible in this shared playlist (either for_client=True or authored by a guest).
GET
/shared/playlists/{token}/attachment-files/{attachment_id}/file/{file_name}
curl \
--request GET 'http://api.example.com/shared/playlists/{token}/attachment-files/{attachment_id}/file/{file_name}' \
--header "Authorization: $API_KEY"