fix: make sure the auth emulator respects multi-tenancy for sso users

[wieringen]

Fixes #8541

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[aalej]

Thanks for creating this PR! I've tested the changes and verified that the users are now getting created in the correct tenants. Let me try to ask someone from our engineering team to review this.

Could you add a CHANGELOG.md entry for this change?

[wieringen]

Done, thanks a lot!

[joehan]

Looks like you need to fix merge conflicts with the CHANGELOG and then run npm run format, but otherwise this looks good to me! Thanks for the contribution

[wieringen]

@joehan done :)