Dazel docker builds failing: unable to download base image

[CodingCanuck]

Checks on #511 are failing with what look like unrelated failures.

Sample failure: https://github.com/3rdparty/eventuals/runs/7649786897?check_suite_focus=true

From Dazel Docker Build:

Run dazel version
  dazel version
  shell: /usr/bin/bash --noprofile --norc -e -o pipefail {0}
  env:
    GOOGLE_APPLICATION_CREDENTIALS: service_account_credentials.json
Sending build context to Docker daemon  4.387MB

Step 1/10 : FROM python:3.9-slim-bullseye
Head "https://registry-1.docker.io/v2/library/python/manifests/3.9-slim-bullseye": Get "https://auth.docker.io/token?account=githubactions&scope=repository%3Alibrary%2Fpython%3Apull&service=registry.docker.io": EOF
Error: Process completed with exit code 1.

@FolMing FYI