add how to build the doc with devcontainer. (backport #4757)

[mergify]

closes #4497

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This is an automatic backport of pull request #4757 done by Mergify.

[mergify]

Cherry-pick of fcf9bc5 has failed:

On branch mergify/bp/iron/pr-4757
Your branch is up to date with 'origin/iron'.

You are currently cherry-picking commit fcf9bc50.
  (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:   README.md
	modified:   docker/image/Dockerfile
	new file:   source/The-ROS2-Project/Contributing/images/vscode_devcontainer.png

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	deleted by us:   .devcontainer/devcontainer.json
	both modified:   source/The-ROS2-Project/Contributing/Contributing-To-ROS-2-Documentation.rst

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

[github-actions]

HTML artifacts: https://github.com/ros2/ros2_documentation/actions/runs/11354203107/artifacts/2060308201.

To view the resulting site:

1. Click on the above link to download the artifacts archive
2. Extract it
3. Open html-artifacts-4810/index.html in your favorite browser