Convert //thrift/... from 3rd party mock
Convert //thrift/... from 3rd party mock

Summary: Removed pypi mock for built in unittest.mock

Reviewed By: junzh0u

Differential Revision: D36167337

fbshipit-source-id: 86dfa411c7906b24a23fa8a14b111c44f841da70

facebook/fbthrift,facebook/fbthrift,facebook/fbthrift,facebook/fbthrift,facebook/fbthrift,facebook/fbthrift,facebook/fbthrift,facebook/fbthrift,facebook/fbthrift