b2778dae70
Fix remote images being chosen over the local ones we just built with
Complement in CI (any Docker environment using the `containerd` image
store). This problem means that Complement jobs in CI don't actually
test against the code from the PR (since 2026-02-10).
This PR approaches the problem the same way that @AndrewFerr proposed in
https://github.com/element-hq/synapse/pull/18210. This is better than
the alternative listed below as we can just make our code compatible
with whatever image store is being used.
### Problem
Spawning from
https://github.com/element-hq/synapse/pull/19460#discussion_r2818760635
where we found that our Complement jobs in CI don't actually test
against the code from the PR at the moment.
This is caused by a change in Docker Engine 29.0.0:
> `containerd` image store is now the default for **fresh installs**.
This doesn't apply to daemons configured with `userns-remap` (see
[moby#47377](https://github.com/moby/moby/issues/47377)).
>
> *-- 29.0.0 (2025-11-10),
https://docs.docker.com/engine/release-notes/29/#2900*
And our `ubuntu-latest` GitHub runner (`Current runner version:
'2.331.0'`)
[points](https://github.com/actions/runner-images/blob/ubuntu24/20260209.23/images/ubuntu/Ubuntu2404-Readme.md)
to using Docker client/server `29.1.5` 🎯
This Docker version bump happened on
416418df15
(2026-02-10) (`28.0.4` -> `29.1.5`). Specific PR:
https://github.com/actions/runner-images/pull/13633
---
I found this because I reviewed and remembered
https://github.com/element-hq/synapse/pull/18210 was a thing that
@AndrewFerr ran into. And then running `dockers system prune` also
revealed the problematic `containerd` in CI. Checking the Docker
changelogs, I found the new default culprit and then could trace down
where the GitHub runners made the dependency update.
---------
Co-authored-by: Andrew Ferrazzutti <andrewf@element.io>