RLS GroupName: SNAdmins, SNUsers?

I am inspecting the SQL generated for RLS, and I am seeing the following:

WHERE ("UserName" IN ('foo@example.com', '') OR "UserName" IS NULL)
AND ("GroupName" IN ('SNAdmins', 'SNUsers', '') OR "GroupName" IS NULL)

What are SNAdmins and SNUsers values? These aren’t coming from our solution.

Thanks.

QuickSight team is looking into this.