code: public static LocalDate randomLocalDateBefore(LocalDate before) {
      checkArgument(before != null, "Before must be non-null");
      Instant instant = randomInstantBefore(before.atStartOfDay(UTC).toInstant());
      return instant.atZone(UTC).toLocalDate();
    }
docs: Returns a random {@link LocalDate} that is before the given {@link LocalDate}.
  
  @param before the value that returned {@link LocalDate} must be before
  @return the random {@link LocalDate}
  @throws IllegalArgumentException if before is null or if before is equal to or before {@link
  RandomDateUtils#MIN_INSTANT}