Defines a custom error message used by CreateScanConfig and
UpdateScanConfig APIs when scan configuration validation fails. It is
also reported as part of a ScanRunErrorTrace message if scan validation
fails due to a scan configuration error.
Output only. Indicates the full name of the ScanConfig field
that triggers this error, for example "scan_config.max_qps".
This field is provided for troubleshooting purposes only and
its actual value can change in the future.
