Update and adjust OIDC documentation. This also adds information for users about RP's that have been tested.
Co-authored-by: Georg Lauterbach <44545919+aendeavor@users.noreply.github.com>
Co-authored-by: Clément Michaud <clement.michaud34@gmail.com>
Co-authored-by: Amir Zarrinkafsh <nightah@me.com>
Co-authored-by: James Elliott <james-d-elliott@users.noreply.github.com>
