Update SSO guide

[Haarolean]

Added information from #1017

• Breaking change? (if so, please describe the impact and migration path for existing applications:)

What changes did you make? (Give an overview)

Is there anything you'd like reviewers to focus on?

How Has This Been Tested? (put an "X" next to an item)

• No need to
• Manually(please, describe, when necessary)
• Unit checks
• Integration checks
• Covered by existing automation

Checklist (put an "X" next to an item, otherwise PR will fail)

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (e.g. ENVIRONMENT VARIABLES)
• My changes generate no new warnings(e.g. Sonar is happy)
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged

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