Update documentation for Content Security Policy (CSP)

[Erasure5959]

Update relevant documentation to reflect new defaults for the Content Security Policy (CSP) after hardening.

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What does this PR aim to accomplish?:

This change aims to update the documentation for the default Content Security Policy as proposed in the FTL repository.

How does this PR accomplish the above?:

Update relevant documentation to reflect new defaults for the Content Security Policy (CSP) after hardening.

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[DL6ER]

@PromoFaux is this supposed to automagically update or is this PR needed?

[PromoFaux]

There will be an automagic PR once the FTL changes are merged to master.

[rdwebdesign]

The proposed FTL changes will only be effective after the next FTL release, which will automatically trigger the change here. So, this PR is not needed.

Also, [configfile.md] file contains a header explaining changes will be auto-generated:

docs/docs/ftldns/configfile.md

Lines 1 to 5 in 57fd4b7

	<!--!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
	! DO NOT EDIT THIS FILE MANUALLY! !
	! THIS FILE IS AUTO-GENERATED FROM THE FTL REPO !
	!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
	-->

[github-actions]

This pull request has conflicts, please resolve those before we can evaluate the pull request.

[yubiuser]

This PR should be superseded by #1351