Renamed a TensorListMetaData property. Cleaned up a test (#46662)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/46662
Test Plan: Imported from OSS
Reviewed By: ansley
Differential Revision: D24453346
Pulled By: izdeby
fbshipit-source-id: f88ac21708befa2e8f3edeffe5805b69a4634d12