Clear origin when copying move

If the copy is not a split, we should remove the invoice line origin as it is
new move that should be invoiced.

issue7657
review64531002

stock.py

@@ -248,6 +248,21 @@ class Move(metaclass=PoolMeta):
     def cancel(cls, moves):
         super(Move, cls).cancel(moves)
 
+    @classmethod
+    def copy(cls, moves, default=None):
+        pool = Pool()
+        InvoiceLine = pool.get('account.invoice.line')
+        moves = super(Move, cls).copy(moves, default=default)
+        if not Transaction().context.get('_stock_move_split'):
+            to_save = []
+            for move in moves:
+                if isinstance(move.origin, InvoiceLine):
+                    move.origin = None
+                    to_save.append(move)
+            if to_save:
+                cls.save(to_save)
+        return moves
+
 
 class ShipmentInternal(metaclass=PoolMeta):
     __name__ = 'stock.shipment.internal'