Update Cocoapods to 1.4.0 (#30326)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/30326
Note that this PR won't trigger the cocoapods build. We'll push the binary and release the cocoapods after the branch cut.
Test Plan: Imported from OSS
Differential Revision: D18660308
Pulled By: xta0
fbshipit-source-id: 95dd97b7b67e70ecee3a65d8bbc125791872b7ca
