Clarify wording around overrides subclasses. (#51031)
Summary:
Fixes https://github.com/pytorch/pytorch/issues/47117
Pull Request resolved: https://github.com/pytorch/pytorch/pull/51031
Reviewed By: bdhirsh
Differential Revision: D26047498
Pulled By: albanD
fbshipit-source-id: dd0a7d9f97c0f6469b3050d2e3b4473f1bee3820
