[Backport 6.6.x] update registries and fix docker login#1265

burmudar merged 2 commits intomainsourcegraph/deploy-sourcegraph-docker:mainfrom

wb/backport-1264-to-6.6.xsourcegraph/deploy-sourcegraph-docker:wb/backport-1264-to-6.6.xCopy head branch name to clipboard