public static String formatUnixTimestamp(long unixtime, TimeZone tz) {
    return formatUnixTimestamp(unixtime, TIMESTAMP_FORMAT_STRING, tz);
  }
Convert unix timestamp (seconds since '1970-01-01 00:00:00' UTC) to datetime string in the
"yyyy-MM-dd HH:mm:ss" format.
amoro-format-mixed/amoro-mixed-flink/amoro-mixed-flink-common/src/main/java/org/apache/amoro/flink/util/DateTimeUtils.java