Right now, we're not using zdicts for the F34 zchunk metadata because
they were only added in fedora-repo-zdicts-2103.1-2 (which should now
be in the updates repo in all current Fedora releases).
If we could update fedora-repo-zdicts to 2103.1-2 on whichever servers
generate the metadata (preferably before the 34 GA metadata is
generated), that should significantly reduce the size of the metadata.