* Azure OAuth: extract groups from token for teamsync

* Docs: changed some headers

* Azure OAuth: fix tests

* Azure OAuth: fix linter error (simplify)

* Azure OAuth: add allowed_groups option

* Azure OAuth: docs for team sync and allowed_groups

* Azure OAuth: tests for allowed_groups

* Update docs/sources/auth/azuread.md

Co-Authored-By: Leonard Gram <leo@xlson.com>

Co-authored-by: Leonard Gram <leo@xlson.com>