[8.x] Creates CSPM privileges standalone page (backport #6269)

[mergify]

Fixes #6261 — Creates a standalone page that describes the privileges that grant different levels of access to CSPM features. Removes the lists of privileges from the requirements sections of each of the CSPM get started guides for AWS, GCP, and Azure, and replaces them with a link to the new page, which includes more details.

Preview: CSPM privilege requirements ESS, Serverless

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This is an automatic backport of pull request #6269 done by Mergify.

[mergify]

Cherry-pick of 51b58c2 has failed:

On branch mergify/bp/8.x/pr-6269
Your branch is up to date with 'origin/8.x'.

You are currently cherry-picking commit 51b58c2f.
  (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/cloud-native-security/cloud-native-security-index.asciidoc
	modified:   docs/cloud-native-security/cspm-get-started-aws.asciidoc
	modified:   docs/cloud-native-security/cspm-get-started-azure.asciidoc
	modified:   docs/cloud-native-security/cspm-get-started-gcp.asciidoc
	new file:   docs/cloud-native-security/cspm-permissions.asciidoc
	new file:   docs/serverless/cloud-native-security/cspm-permissions.asciidoc

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	deleted by us:   docs/serverless/cloud-native-security/cspm-get-started-azure.asciidoc
	deleted by us:   docs/serverless/cloud-native-security/cspm-get-started-gcp.asciidoc
	deleted by us:   docs/serverless/cloud-native-security/cspm-get-started.asciidoc
	deleted by us:   docs/serverless/index.asciidoc

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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