related() returns stale data after update via external model

[Clon-cz]

Version: 3.2.6

Bug Description

When updating a related row using an external repository/model ($this->order_product->find(...)->update(...)), a subsequent call to $parent->related('...')->fetchAll() returns stale (pre-update) data.

However, if I call $relatedRow->update(...) directly on the row from related(), the update is reflected correctly.

Steps To Reproduce

$order = $this->order_db->find($id);
		if ($order) {
			$opPrice = [];
			foreach ($order->related('order_product')->fetchAll() as $op) {
				$opPrice[$op->id]['original'] = $op->price;
//$op->update(['price' => rand(0, 100)]); // works
				$product = $this->order_product->find($op->id);
				$opPrice[$op->id]['new'] = rand(0,100);
				$product->update(["price" => $opPrice[$op->id]['new']]);
			}

			foreach ($order->related('order_product')->fetchAll() as $op) {
				$opPrice[$op->id]['wrong'] = $op->price; // still old
				$opPrice[$op->id]['actual'] = $this->order_product->find($op->id)->offsetGet('price'); // correct
			}
			dump($opPrice);
		}

Important detail

This code works

foreach ($order->related('order_product')->fetchAll() as $op) {
    $op->update(['price' => rand(0, 100)]); // then fetchAll() will reflect the change
}

Database schema

•	order: id
•	order_product: id, order_id, product_id, price

Notes

Looks like internal caching of the related(...) result is not cleared or invalidated when updates happen via external fetches.