API Feature Request: Add a separate endpoint to update notes on an order.

[PointOfSaleDev]

Currently the only way to update notes on a order is via the create/update endpoints listed below:

• https://www.shipstation.com/docs/api/orders/create-update-order/
• https://www.shipstation.com/docs/api/orders/create-update-multiple-orders/

However, these endpoints only allow users to update open orders. So you cannot add a note to an order that's been shipped (but you can still do this from the UI). Adding a separate endpoint for inserting/updating notes would resolve that issue.