[CI Runners] include autoscaling into the error ratio metrics

Summary

During production#14628 (closed) our error ratio didn't change, which is not reflecting the errors we were receiving.

Related Incident(s)

Originating issue(s): production#14628 (closed)

Desired Outcome/Acceptance Criteria

Autoscaling has it's own SLI which eventually contributes to the service Apdex.

Associated Services

ServiceCI Runners

Corrective Action Issue Checklist

• Link the incident(s) this corrective action arose out of
• Give context for what problem this corrective action is trying to prevent from re-occurring
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