pytorch

3cc50625 - Update bazel to 3.1.0 (#37951)

Update bazel to 3.1.0 (#37951) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/37951 Differential Revision: D21439260 Pulled By: malfet fbshipit-source-id: 77bcb5a28a29482f6e44c01e3dafd24d24ee7ec3