[oslo][infra] Oslo core security team on Launchpad

Hi, I just noticed that the Oslo core security team includes a number of people no longer active in Oslo and also only me for current cores. We should really clean that up so random people aren't getting notified of private security bugs and ideally add some current cores so we have more eyes on said security bugs. How do we go about doing that? I see it's owned by the OpenStack Administrators team, so do I put in a request with the changes or can they just make me an administrator for that group? Thanks. -Ben