Pantry panic in a4x2: Job completed while not InProgress: Done

[jgallagher]

I was trying to import a disk in a4x2 via this Oxide CLI invocation:

oxide --timeout 120 disk import \
    --path debian-12-genericcloud-amd64.raw \
    --disk bookworm-boot \
    --project prototypes \
    --description "Debian bookworm disk" \
    --snapshot bookworm-snapshot \
    --image bookworm \
    --image-description "Debian bookworm image" \
    --image-os Debian \
    --image-version 12

After not quite 2 minutes it failed with

sending chunk to thread failed: channel closed

which seems similar to the test flake oxidecomputer/omicron#6771, but in this case it looks like the pantry panicked:

thread 'tokio-runtime-worker' panicked at upstairs/src/client.rs:1280:13:
[1] Job 1252 completed while not InProgress: Done DownstairsIO { ... trim a couple megabytes ... }
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
[ Oct 18 18:21:28 Stopping because all processes in service exited. ]

The full pantry log: pantry.log