raise when jit-load.ing a folder (#27836)
Summary:
Very similar to https://github.com/pytorch/pytorch/issues/16267 but handling directories.
Stoked to contribute!
Pull Request resolved: https://github.com/pytorch/pytorch/pull/27836
Differential Revision: D19698398
Pulled By: ezyang
fbshipit-source-id: eabc3a44d258124f860babb47ab91e22c2c3d6cc
