Adds saml auth header to differentiate saml requests and prevents auto login as anonymous user when basic authentication fails#4152

DarshitChanpura merged 12 commits intoopensearch-project:mainopensearch-project/security:mainfrom

DarshitChanpura:saml-anony-bug-fixDarshitChanpura/security:saml-anony-bug-fixCopy head branch name to clipboard