Don't try to sync empty repos
Some repos (cough Rabbitmq cough) are constantly messing up and publishing empty repositories. This will stop reposync from removing all our packages in those cases.
Please be advised that registry.cern.ch and registry-tn.cern.ch registries (Registry Service) will be unavailable next Tuesday, Feb 11th starting at 08:00h (Geneva time) for a short period of time. This may cause temporary disruptions to your workflows. Further info: OTG0154380
Some repos (cough Rabbitmq cough) are constantly messing up and publishing empty repositories. This will stop reposync from removing all our packages in those cases.