Auto set libuv_ROOT env var for Gloo submodule on Windows platform (#45484)
Summary:
Fixes #{issue number}
Pull Request resolved: https://github.com/pytorch/pytorch/pull/45484
Reviewed By: lw
Differential Revision: D23990724
Pulled By: mrshenli
fbshipit-source-id: 1987ce7eb7d3f9d3120c07e954cd6581cd3caf59
