OpenAPI Update (#887)

Update OpenAPI for 9564bf249dee65e55f5b282e926f21419f2ef5f1

Co-authored-by: Stripe OpenAPI <105521251+stripe-openapi[bot]@users.noreply.github.com>

embedded/openapi/spec3.beta.sdk.json

@@ -82279,7 +82279,7 @@
         }
       },
       "post": {
-        "description": "<p>Create a margin object to be used with invoices, invoice items, and invoice line items for a customer to represent a partner discount.A margin has a <code>percent_off</code> which is the percent that will be taken off the subtotal after all items and other discounts and promotions) of any invoices for a customer. Calculation of prorations do not include any partner margins applied on the original invoice item.</p>",
+        "description": "<p>Create a margin object to be used with invoices, invoice items, and invoice line items for a customer to represent a partner discount. A margin has a <code>percent_off</code> which is the percent that will be taken off the subtotal after all items and other discounts and promotions) of any invoices for a customer. Calculation of prorations do not include any partner margins applied on the original invoice item.</p>",
         "operationId": "PostBillingMargins",
         "requestBody": {
           "content": {