update Time
The most recent time at which the BigQuery export was updated. This field is set by the server and will be ignored if provided on export creation or update. A timestamp in RFC3339 UTC "Zulu" format, with nanosecond resolution and up to nine fractional digits. Examples: "2014-10-02T15:01:23Z" and "2014-10-02T15:01:23.045123456Z".