[Saved Objects] Documents intended use of removeReferencesTo

[jeramysoucy]

Summary

Updates comments for removeReferencesTo (SO Repository) and authorizeRemoveReferences (SO Security Extension) methods with remarks regarding the intended use and authorization.

Currently the only use case for removeReferencesTo is the delete method of the tags client. If the authorization check is changed to authorize an update for each referencing object, lingering references in objects which the user is not authorized to update may be left behind when a tag is deleted. We will leave the current implementation in place until a decision about if & how to manage referential integrity occurs.

This PR documents the current intended use case for removeReferencesTo as: "to provide clean up of any references to an object which is being deleted (e.g. deleting a tag)."

See issue #135259 and discussion here, for background.

[jeramysoucy]

@elasticmachine merge upstream

[kibanamachine]

expected head sha didn’t match current head ref.

[kibana-ci]

💚 Build Succeeded

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• Commit: e2faf13

Metrics [docs]

Unknown metric groups

ESLint disabled line counts

id	before	after	diff
securitySolution	433	436	+3

Total ESLint disabled count

id	before	after	diff
securitySolution	513	516	+3

History

• 💔 Build #115465 failed 10288c5

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@elasticmachine merge upstream

[elasticmachine]

Pinging @elastic/kibana-security (Team:Security)

[pgayvallet]

Thanks for doing this