add dumb retry to installing miniconda (#71558)
Summary:
Potentially can alleviate some issues related to https://github.com/pytorch/pytorch/issues/69730
Pull Request resolved: https://github.com/pytorch/pytorch/pull/71558
Reviewed By: anjali411
Differential Revision: D33686601
Pulled By: janeyx99
fbshipit-source-id: fbf3aa77c2b97237f0080d1d2ae13c997d99b6c1
(cherry picked from commit 94ecd3840104bbb65751a106a642426f412ff4c7)
