[Backport 2.x] Initial commit for multiple authentication#1191

RyanL1997 merged 2 commits into2.xopensearch-project/security-dashboards-plugin:2.xfrom

backport/backport-1110-to-2.xopensearch-project/security-dashboards-plugin:backport/backport-1110-to-2.xCopy head branch name to clipboard