private static long ceil(long a, long b) {
    long r = a % b;
    if (r > 0) {
      return a - r + b;
    } else {
      return a - r;
    }
  }
Keep the algorithm consistent with Calcite DateTimeUtils.julianDateFloor, but here we take time
zone into account.
amoro-format-mixed/amoro-mixed-flink/amoro-mixed-flink-common/src/main/java/org/apache/amoro/flink/util/DateTimeUtils.java