Drop rawtypes warnings from identityprovider (backport of #68249) (#68448)

We barely used it and it makes it easier for us to write code with
"funny" assumptions. This change mostly makes the assumptions more clear
without really changing them.

Co-authored-by: Elastic Machine <elasticmachine@users.noreply.github.com>

Co-authored-by: Elastic Machine <elasticmachine@users.noreply.github.com>