move AWS ECR gc jobs to circleci (#30996)
Summary:
all jobs are currently running with "--dry-run", so you can verify if the jobs are doing the right thing. i'll remove the flag and make it runs every hour same as on Jenkins once this PR is approved.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/30996
Differential Revision: D18971001
Pulled By: mingbowan
fbshipit-source-id: 2384bdb50ebdf47aad265395f26be3843f0ce05e
