Revert "Revert "Temporarily stop sending traffic to 2i2c-bare""

[yuvipanda]

Reverts #3212

It went well! In the time traffic has been going there (~3 days), the disk size of the registry has grown to 134G. I put a 300G limit on that, so we'd have reached that in approximately a week.

So the outcomes are:

1. We can put the registry on disk
2. But we must implement GC of least used images
3. And the GC may have to be aggressive if the disk size allocated to registry is small