[Split shipment] Create shipment network

[atorresveiga]

This task is for adding network support for creating a new package using the latest plugin endpoint
POST /wcshipping/v1/shipments/{order_id}

Here is the endpoint's documentation
https://github.com/woocommerce/woocommerce-shipping/blob/trunk/docs/api/shipments.md

Tasks

• Networking layer [Shipping Labels] Update shipment endpoint - Networking layer #15445
• Yosemite layer [Shipping Labels] Update shipment endpoint - Yosemite layer #15446
• Create shipments from the view model [Shipping Labels] Update shipments from view layer #15449

[dangermattic]

🚫 Please add a type label (e.g. type: enhancement) and a feature label (e.g. feature: stats) to this issue.