stats_from_file_desc_list: dont manually zip list

[matthiaskrgr]

use use x.iter().zip(x.iter().skip(1))

pub fn main() {
    let i = &[1, 2, 3, 4, 5, 6];

    i.iter()
        .zip(i.iter().skip(1))
        .for_each(|(a, b)| println!("{} {}", a, b));
}

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