[Reland] Replacing the p.data acccess in utils with tensor.set_ . Passes both test_po...

[Reland] Replacing the p.data acccess in utils with tensor.set_ . Passes both test_post_localSGD_optimizer_pari and test_periodic_model_averager tests (#63895)

Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/63895

When updating the model parameter, updating `parameter.data` is no longer recommended, because this `data` field will be deprecated in the future.

The replacement is `tensor.set_`.
ghstack-source-id: 136593433

Test Plan:
buck test mode/dev-nosan //caffe2/test/distributed:distributed_nccl_spawn -- test_periodic_model_averager
buck test mode/dev-nosan //caffe2/test/distributed:distributed_nccl_spawn -- test_post_localSGD_optimizer_parity

Reviewed By: SciPioneer

Differential Revision: D30526178

fbshipit-source-id: a1ac0ec3665d8623edd5bf94f01c1132daff5c00