bug: thread panic "missing function core::array::ArrayIterator::<core::integer::u8>::advance_by"

[cairoIover]

Bug Report

Cairo version:
6e8795a

Current behavior:
Trying to implement advance_by after #7027 was merged:

/// An iterator over a collection of values.
pub trait Iterator<T> {
    /// The type of the elements being iterated over.
    type Item;

    /// Advance the iterator and return the next value.
    fn next(ref self: T) -> Option<Self::Item>;

    fn advance_by(ref self: T, n: usize) -> Result<(), NonZero<usize>> {
        let mut res = Result::Ok(());
        for i in 0..n {
            if Self::next(ref self).is_none() {
                res = Result::Err((n - i).try_into().unwrap());
                break;
            }
        };
        res
    }
}

Added an associated test:

#[test]
fn test_advance_by() {
    let a = array![1_u8, 2, 3, 4];
    let mut iter = a.into_iter();

    assert_eq!(iter.advance_by(2), Result::Ok(()));
    assert_eq!(iter.next(), Option::Some(3));
    assert_eq!(iter.advance_by(0), Result::Ok(()));
}

The implementation of Iterator stays the same: it should leverage the default trait impl

impl ArrayIterator<T> of Iterator<ArrayIter<T>> {
    /// The type of the elements being iterated over.
    type Item = T;
    /// Advances the iterator and returns the next value. Returns `Option::None` when iteration is
    /// finished.
    fn next(ref self: ArrayIter<T>) -> Option<T> {
        self.array.pop_front()
    }
}

Running the tests panics with:

thread '<unnamed>' panicked at crates/cairo-lang-sierra-generator/src/utils.rs:331:13:
Missing function core::array::ArrayIterator::<core::integer::u8>::advance_by
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
thread 'main' panicked at crates/cairo-lang-sierra-generator/src/utils.rs:331:13:
Missing function core::array::ArrayIterator::<core::integer::u8>::advance_by

Expected behavior:
The test should run successfully - or a clear error message returned