[8.1] Updates warning about editing rules using API authentication (backport #4110)

[mergify]

This is an automatic backport of pull request #4110 done by Mergify.
Cherry-pick of 783ce5a has failed:

On branch mergify/bp/8.1/pr-4110
Your branch is up to date with 'origin/8.1'.

You are currently cherry-picking commit 783ce5a.
  (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:   docs/detections/api/rules/rules-api-overview.asciidoc
	modified:   docs/detections/api/rules/rules-api-update.asciidoc

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   docs/detections/api/rules/rules-api-bulk-actions.asciidoc
	both modified:   docs/detections/api/rules/rules-api-create.asciidoc
	both modified:   docs/detections/api/rules/rules-api-import.asciidoc

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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