Only upload files

[pathurs]

If a folder ends with .js, .jsx, or .js.map, it will attempt to upload it, throwing an error:

Error: EISDIR: illegal operation on a directory, read
Emitted 'error' event on ReadStream instance at:
    at internal/fs/streams.js:202:14
    at FSReqCallback.wrapper [as oncomplete] (fs.js:528:5) {
  errno: -4068,
  code: 'EISDIR',
  syscall: 'read'
}