We already configure the trixie keys so don't need to add new keys. Go
ahead and add reprepro configuration to mirror trixie, trixie-updates,
trixie-backports, and trixie-security. This is currently the easiest
workaround for managing mirrors on the new trixie test nodes since
bookworm and bullseye are mirrored.
Thankfully recent efforts by fungi have cleared out space on our AFS
system which means we should have plenty of room for trixie.
Change-Id: I558c01fdc0e2fb26cfc4827e9e03d73fad0d98aa
b8776128e0