Add clarifying information to SSO docs

### Contributions

- [X] I have read the contribution docs, and understand what's expected of me.

### Link to the page on docs.getdbt.com requiring updates

User reported the following feedback for SSO documentation to @b-per :

- User used OneLogin docs and followed the instructions set out in the OneLogin SSO docs. They struggled to get the group mapping to work as our docs don’t provide specific info about OneLogin setup
- the audit log is not giving information about the groups assigned to the users, making it difficult to troubleshoot

I am sure that they’d be happy to have a chat with the doc team to add a couple of screenshots.

### What part(s) of the page would you like to see updated?

[OneLogin SSO documentation](https://docs.getdbt.com/docs/cloud/manage-access/set-up-sso-saml-2.0#onelogin-integration)

### Additional information

_No response_