Summary:
Add an extra cleanup step so that db directory can be saved and uploaded.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5554
Reviewed By: yancouto
Differential Revision: D16168844
Pulled By: riversand963
fbshipit-source-id: ec7b2cee5f11c7d388c36531f8b076d648e2fb19