[native] Show a menu button next to each role except admins

Summary:
To prepare for editing and deleting roles, we want to display a menu button next to each role except for admins. It's safe to check by name here since the Admins role cannot be renamed, but it's worth noting that a more sound check would be what is described in ENG-4155. For now though, I don't think it makes sense to
prioritize this and will be easy enough to update down the line once ENG-4155 is complete

Part of ENG-4367.

Depends on D8502

Test Plan:
Confirmed that the menu button displays for Members and custom roles, but not Admins

Reviewers: atul, ginsu

Reviewed By: ginsu

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D8522