chore(docs): Updated API Reference (v2) (#9148)

Automated changes by [create-pull-request](https://github.com/peter-evans/create-pull-request) GitHub action

Co-authored-by: Oli Juhl <59018053+olivermrbl@users.noreply.github.com>

www/apps/api-reference/specs/admin/components/schemas/AdminFulfillmentItem.yaml

@@ -1,5 +1,5 @@
 type: object
-description: The item's items.
+description: The details of a fulfillment's item.
 x-schemaName: AdminFulfillmentItem
 required:
   - id
@@ -25,11 +25,11 @@ properties:
   quantity:
     type: number
     title: quantity
-    description: The item's quantity.
+    description: The item's quantity to be fulfilled.
   sku:
     type: string
     title: sku
-    description: The item's sku.
+    description: The item's SKU.
   barcode:
     type: string
     title: barcode
@@ -37,27 +37,27 @@ properties:
   line_item_id:
     type: string
     title: line_item_id
-    description: The item's line item id.
+    description: The ID of the order's line item to be fulfilled.
   inventory_item_id:
     type: string
     title: inventory_item_id
-    description: The item's inventory item id.
+    description: The ID of the inventory item of the underlying product variant.
   fulfillment_id:
     type: string
     title: fulfillment_id
-    description: The item's fulfillment id.
+    description: The ID of the fulfillment the item belongs to.
   created_at:
     type: string
     format: date-time
     title: created_at
-    description: The item's created at.
+    description: The date the item was created.
   updated_at:
     type: string
     format: date-time
     title: updated_at
-    description: The item's updated at.
+    description: The date the item was updated.
   deleted_at:
     type: string
     format: date-time
     title: deleted_at
-    description: The item's deleted at.
+    description: The date the item was deleted.