Remove C++11 compatibility from c10::optional (#30919)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/30919
deletecode
ghstack-source-id: 96383227
Test Plan: waitforsandcastle
Differential Revision: D18869641
fbshipit-source-id: c08345d17a291cea3749af20473b6acddc78ab27
