Approval group members are not visible to MR creator, if they do not have membership (or inherited membership) of that group
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Full report by @jweaver-strive: https://gitlab.com/gitlab-org/gitlab/-/issues/255981#note_1029916923
I have the following:
```
top level group:
-- saml groups:
-- Developers
-- Security Approvers (direct membership only)
-- projects group:
-- example project
-- Developers: Developer perm
-- Security approvers: Developer perm and approvers for Scan Results policy
```
In my situation, there is no direct nor inherited membership for the Developers as pertains to the `Security Approvers` group. This results in a empty list of approvers when a Scan Results policy approval is triggered.
What would be the best way to get the `Developers` visibility into who the `Security Approvers` are?
So, generally... there are user groups specifically used for SAML Group Link, and those user groups are then assigned to either projects, or groups containing projects.
My desire isn't to add more members to the Security Approvers group, but rather to permit those who are not a member of the group to still be able to view potential Approvers in their MRs.
<details><summary>See the below screenshot for an example of what a non-Security Approvers group member sees</summary>

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To get around the lack of visibility into approvers, my thought was to simply direct users to post in a Slack channel, but that is not ideal.
__Consider making the proposed behaviour opt-in__, since it allows leaking group membership (see https://gitlab.com/gitlab-org/gitlab/-/issues/368487#note_2082102454)
### Steps to reproduce / example project
https://gitlab.com/gitlab-org/gitlab/-/issues/457490#note_1877886794
issue