chore(deps): update buildkite plugin docker to v5.12.0

[renovate]

This PR contains the following updates:

Package	Update	Change
docker	minor	v5.11.0 -> v5.12.0

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Release Notes

buildkite-plugins/docker-buildkite-plugin (docker)

v5.12.0: (🥐 Medialuna XL)

Compare Source

Added:

• Codeowners (#​273) @​tomowatt
• Job api mounting (#​275) @​toote
• Workdir interpolation (#​276) @​toote
• Add chown setting to fix root permissions on exit (#​278) @​HackAttack

Fixed:

• Fix eval of exit code returned from docker image pull (#​280) @​petetomasik

Upgrading

To upgrade, update your pipeline.yml files:

steps:
  - command: test.sh
    plugins:
-     docker#v5.11.0:
+     docker#v5.12.0:
        image: someimage
        workdir: /app

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Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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• If you want to rebase/retry this PR, check this box

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