Add address to orders that do not require shipping

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5

Just to round out this answer, if you change the URL to what REST requires and method to “PUT”, the REST order update is a bit easier to read.

URL:

https://YOURSTORE.myshopify.com/admin/api/2023-04/orders/{{ order.legacyResourceId }}.json

Body:

{"order":{"id":{{ order.legacyResourceId }},"shipping_address":{"address1":"123 Flow Street","city":"Shipsville"}}}