Change: Use (old)stable for release Docker images (backport #2016)

[mergify]

This is an automatic backport of pull request #2016 done by Mergify.
Cherry-pick of f3cf64f has failed:

On branch mergify/bp/stable/pr-2016
Your branch is up to date with 'origin/stable'.

You are currently cherry-picking commit f3cf64fe7.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   .docker/build.Dockerfile

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   .github/workflows/build-container.yml
	both modified:   .github/workflows/container.yml

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/github/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

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[github-actions]

Conventional Commits Report

Type	Number
Changed	1

🚀 Conventional commits found.