Fix typos. (#45195)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/45195
Fix some typos in reducer class.
ghstack-source-id: 112673443
Test Plan: N/A
Reviewed By: rohan-varma
Differential Revision: D23862399
fbshipit-source-id: 0dc69e5ea1fa7d33c85d1909b2216bcd1f579f6a
