stock_release_channel: do not 'write' records in '_compute_picking_co…

…unt'

This is triggering concurrency updates on release channel records while
reading them in the dashboard (updating `write_date` + `write_uid`
fields).

stock_release_channel/models/stock_release_channel.py

@@ -386,7 +386,7 @@ def _compute_picking_count(self):
                     + values[f"{prefix}_picking_released"]
                     + values[f"{prefix}_picking_done"]
                 )
-            record.write(values)
+            record.update(values)
 
     def _query_get_chain(self, pickings):
         """Get all stock.picking before an outgoing one