Git index slow to update

The background worker has been told to get itself together. The queue is now trending downwards, but git index updates are still running an hour behind. We are continuing to monitor, but we expect this to resolve over the next few hours.

The crates.io background worker is having a bad morning, and a backlog of Git index updates has accumulated. We have given the worker some coffee and it's catching up, but index updates for newly-published crates are running about an hour behind right now.

The sparse index (used by default by all modern Rust versions) is unaffected.