fix clang-tidy warning - make global TorchLibraryInit objects const (#48956)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/48956
ghstack-source-id: 118140666
Test Plan: GitHub CI
Reviewed By: ezyang
Differential Revision: D25381418
fbshipit-source-id: 1726ed233b809054cb9e5ba89e02c84fb868c1eb
