Deleting an order line fails without mod-invoice

Purpose/Overview:

Mod-orders should not depend on mod-invoice for basic operations, but:

DELETE /orders/order-lines/{{orderLineId}}

returns the error:

"No suitable module found for path /invoice/invoice-lines for tenant diku"

This is caused by PurchaseOrderLineHelper#deleteLine calling PurchaseOrderLineHelper#verifyDeleteAllowed calling OrderInvoiceRelationService#checkOrderPOLineLinkedToInvoiceLine.

Requirements/Scope:

Ensure that deleting an order line can be done without mod-invoice installed.

Approach:

In checkOrderPOLineLinkedToInvoiceLine(), check that the order is linked to some invoice with getOrderInvoiceRelationshipCollection() before proceeding with the invoice line query. Return right away if there is no relationship.

Acceptance criteria:

• Test with Postman (Karate tests for mod-orders might include mod-invoice)