Update order status to "Closed" from invoice/payment flow

Overview:
PO status should be updated to "Closed" by the invoicing/payment flow if:

• all PoLines have:

  (paymentStatus == "Not required" OR paymentStatus == "Fully paid") 
  AND 
  (receivingStatus == "Fully received" OR receivingStatus == "Receiving not required")
  

Dennis Bridges to check with the small group on whether a notification is required/desired in this case, and the preferred mechanism for such notifications (toast/email/confirmation modal/etc.)

Acceptance criteria:

• The business logic described above has been implemented
• Unit tests have been updated
• API tests have been updated