Adding sub day seconds to Date64 is ignored.

[tshauck]

Describe the bug

The second part of add_month_day_nano is seemingly ignored, so if you try to add like an hour to a Date64Type, you actually get back the same date.

To Reproduce

This test will pass on main, but it shouldn't (added to arrow-array/src/types.rs).

#[cfg(test)]
mod tests {
    use super::*;
    use arrow_data::{layout, BufferSpec};

    #[test]
    fn add_month_day_nano() {
        let date_64 = Date64Type::default_value();
        let interval = IntervalMonthDayNanoType::make_value(0, 0, 1_000_000_000 * 3600);

        let result = Date64Type::add_month_day_nano(date_64, interval);

        // result equals date_64, but should be an hour after.
        assert_eq!(result, date_64);
    }
}

Expected behavior

For date64s adding increments less than a day should be supported.

Additional context

I think the result is from coercion to a NaiveDate instead of a NaiveDateTime. I have a working branch, I'll open a PR for... https://github.com/apache/arrow-rs/compare/master...tshauck:add-sub-day-increments-to-date64type?expand=1

[tustvold]

See discussion on #6199

[alamb]

label_issue.py automatically added labels {'arrow'} from #6199