we should retire the 'rpm packaging' trac component

[I'm starting this ticket out in the Tor component, so it can get an opinion from the network team folks before it moves to the Trac component.]

We have a trac component "Core Tor / RPM packaging", which up until yesterday had zero open tickets in it, and currently has one: https://trac.torproject.org/projects/tor/query?status=accepted&status=assigned&status=merge_ready&status=needs_information&status=needs_review&status=needs_revision&status=new&status=reopened&component=Core+Tor%2FRPM+packaging&col=id&col=summary&col=status&col=type&col=priority&col=milestone&col=component&order=priority

Hiviah is long gone as our RPM maintainer, meaning we don't have one -- or rather, meaning we are at the mercy of whatever maintainer fedora and centos decide, or don't decide, to have for themselves.

Having an RPM packaging component on our trac can mislead people into thinking that we have people looking at our trac who might work on RPM packaging.

We should move the component to the trac attic, like other components that have lived a happy life but now it's time for them to move on.