[13.x] Add insertOrIgnoreReturning() to the Eloquent builder passthru

[xurshudyan]

insertOrIgnoreReturning() was added to the query builder in #59025 but never added to the Eloquent builder's $passthru, so on a model the returned rows are lost:

$new = Tag::insertOrIgnoreReturning([
    ['name' => 'php'],
    ['name' => 'laravel'],
], ['id', 'name']);

$new->pluck('id');
// today: runs "select id from tags" and returns every tag in the table
// expected: the ids that were just inserted

The insert itself works, only the return value is wrong. DB::table('tags') is unaffected.