Fix hash type (#46769)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/46769
Value to be hashed is `int64_t`, but hash is `int`. This results in a downconversion which throws out bits which would otherwise be hashed.
Test Plan: Standard pre-commit test rig
Reviewed By: malfet
Differential Revision: D24480962
fbshipit-source-id: 497b1d8bc3f6d2119a6ba16e6ae92911bd34b916
