curl --request PATCH \
  --url https://clarus-api.com/api/integration_product_mapping_groups/{mapping_group_id}/mappings/{id} \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --header 'X-Clarus-Subdomain: <api-key>' \
  --data '
{
  "data": {
    "type": "integration_product_mappings",
    "attributes": {
      "product_id": 1024,
      "integration_product_id": 778,
      "mapping_fields": [
        {
          "sku": "EXT-SKU-99"
        }
      ]
    }
  }
}
'

{
  "error": "<string>"
}