[FIX] point_of_sale,pos_sale: correctly load last order after refresh

[robinengels]

After parking an order, if you refresh the page the parked order would be selected as the current order.

Steps to reproduce:

• Setup a PoS with atleast one trusted PoS
• Open the PoS and add some products to the order
• Park the order
• Refresh the page

Observation: The parked order is selected

Why the fix:

When setting the start order we take the last order saved instead of the first one.

opw-4104298

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[robodoo]