Switch default memory format of clone operator to Preserve
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/30089
Test Plan: Imported from OSS
Differential Revision: D18624985
Pulled By: VitalyFedyunin
fbshipit-source-id: 8d315b08b7b5858fd0a81d3375b44ccb94787ad4
