Populate avatar from SAML attribute

[soumplis]

It would be nice if we could populate / update a user's profile info by releasing extra attributes from the IdP to nextcloud.

[imacks]

+1

Populating the avatar would be awesome

[Lumrenion]

I would like to populate the avatar url from SAML as well. It might be helpful to take a look at user_dap and see how they implemented this. Mind, if I dig into this?