Doc update (backport #3532)

[mergify]

Updating to a more accurate description of the expected output (both cpp and py versions).

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This is an automatic backport of pull request #3532 done by Mergify.

[mergify]

Cherry-pick of 8a6ad2f has failed:

On branch mergify/bp/humble/pr-3532
Your branch is up to date with 'origin/humble'.

You are currently cherry-picking commit 8a6ad2f.
  (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)

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   source/Tutorials/Beginner-Client-Libraries/Using-Parameters-In-A-Class-CPP.rst
	both modified:   source/Tutorials/Beginner-Client-Libraries/Using-Parameters-In-A-Class-Python.rst

no changes added to commit (use "git add" and/or "git commit -a")

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

[fujitatomoya]

lgtm with green CI.

[github-actions]

HTML artifacts: https://github.com/ros2/ros2_documentation/actions/runs/15448492413/artifacts/3261165710.

To view the resulting site:

1. Click on the above link to download the artifacts archive
2. Extract it
3. Open html-artifacts-5696/index.html in your favorite browser