User visibility outside Org segregation: authorized members

[nino-filigran]

Description

Without org segregation, when platform is set to not disclose users pertaining to othr orgs, you can still see them in Authorized member.

Environment

Latest

Reproducible Steps

Steps to create the smallest reproducible scenario:

1. Go in a platform without paltform org
2. Ensure that Allow users to view users of other organizations is not enabled
3. Create a draft with a user via step by step, until you reach th step where you can define authorized members

Expected Output

You can only see users from your own org or without org.

Actual Output

You can see all users.

Additional information

Applies to all the place where Authorized Members can be set.

Screenshots (optional)

[nino-filigran]

Related to initial fix: #15158