[System] Mark logs-system.syslog data stream as requires root

[kpollich]

Proposed commit message

Mark logs-system.syslog data stream as requires root

Reading syslog files requires root, so if this data stream is in use the agent will require root privileges. Adding agent.privileges.root: true makes Fleet/Agent aware of the requirement for escalated privileges.

Checklist

• I have reviewed tips for building integrations and this pull request is aligned with them.
• I have verified that all data streams collect metrics or logs.
• I have added an entry to my package's changelog.yml file.
• I have verified that Kibana version constraints are current according to guidelines.

How to test this PR locally

Run an agent with the system integration and verify it collects data when run as a root user. I don't think the majority of the non-root agent work is "wired up" so there won't be anything obvious to test at this time. See elastic/kibana#183283.

Related issues

Closes #9886

[kpollich]

cc @nimarezainia

[kpollich]

Note the formatting in the diff is just the result of elastic-package check as far as I can tell, but maybe my editor autoformatted these files? I don't recall opening anything other than the main system manifest.yml and syslog/manifest.yml though so my editor didn't touch those files AFAIK. 🤷

[juliaElastic]

LGTM

[elasticmachine]

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[elasticmachine]

💚 Build Succeeded

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• Commit: 94f9868

cc @kpollich

[elastic-sonarqube]

Quality Gate passed

Issues
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0 Accepted issues

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[elasticmachine]

Package system - 1.58.0 containing this change is available at https://epr.elastic.co/search?package=system