[8.x] Use correct technical preview tags (backport #1514)

[mergify]

This updates a few spots in the command reference to use the super handy, inline "technical preview" tag which I didn't know we had.

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This is an automatic backport of pull request #1514 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of b5ea761 has failed:

On branch mergify/bp/8.x/pr-1514
Your branch is up to date with 'origin/8.x'.

You are currently cherry-picking commit b5ea7614.
  (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:   docs/en/ingest-management/commands.asciidoc

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

[github-actions]

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[mergify]

This pull request is now in conflict. Could you fix it @mergify[bot]? 🙏
To fixup this pull request, you can check out it locally. See documentation: https://help.github.com/articles/checking-out-pull-requests-locally/

git fetch <remote-repo>
git checkout -b mergify/bp/8.x/pr-1514 <remote-repo>/mergify/bp/8.x/pr-1514
git merge <remote-repo>/8.x
git push <remote-repo> mergify/bp/8.x/pr-1514