[FIX] purchase_stock: old PO not update qty_received after install purchase_stock

Before this commit, after install purchase_stock, old pol records won't
update their qty_received when receive products. This is because their
qty_received_method are not updated during the installation.

Task 2230811
PR #49921

addons/purchase_stock/data/purchase_stock_data.xml

@@ -2,6 +2,8 @@
 <odoo>
     <data noupdate="1">
 
+        <function model="purchase.order.line" name="_update_qty_received_method" />
+
 		<!--
              Stock rules and routes
         -->

addons/purchase_stock/models/purchase.py

@@ -510,3 +510,8 @@ class PurchaseOrderLine(models.Model):
                     incoming_moves |= move
 
         return outgoing_moves, incoming_moves
+
+    @api.model
+    def _update_qty_received_method(self):
+        """Update qty_received_method for old PO before install this module."""
+        self.search([])._compute_qty_received_method()