[12.x] Feature: Array partition

[liamduckett]

Hey, this PR adds a partition method to the Array helper.

This allows using the existing partition logic, without needing to reach for collections.

// Pre code:
$numbers = [0, 1, 2, 3, 4, 5];

// Before:
[$evens, $odds] = collect($numbers)->partition(fn(int $number) => $number % 2 === 0);

// After:
[$evens, $odds] = Arr::partition($numbers, fn(int $number) => $number % 2 === 0);

I also converted the existing Collection::partition to use the Arr::partition method, to prevent duplication. Happy to revert this bit if preferable.

[pandiselvamm]

Suggestion:

foreach ($array as $key => $item) {
        ($callback($item, $key) ? $passed : $failed)[$key] = $item;
}

[taylorotwell]

@liamduckett do you mind sending some docs over for this?

[liamduckett]

Thanks @pandiselvamm. Speedy!