Missing TaxCollection field in OrderItems response

[pulkitjuneja-1216]

Problem description:

I am using Jlevers version 5.1 and PHP version 7.3. When making a call to OrderItesm API, I am not receiving all the fields one such field is "TaxCollection", which is very important to handle "MarketplaceFacilitator". I went through SPAPI docs as well

Error:

Not receiving any error, just some fields are missing from the response of order items

# Your error here. PLEASE make sure to redact secrets from your error log!

Code

// Your code here...PLEASE make sure to redact secrets from your code!
 $data_elements = array('buyerInfo' );
``` $result = $apiInstance->getOrderItems($order_id, null, $data_elements);

## Seller Central SP API config page screenshot

*your screenshot here*

Screenshot of sample data of order items from Amazon SPAPI docs
![image](https://github.com/jlevers/selling-partner-api/assets/132678631/9a69f7ae-2c3a-4907-8fa9-fdd91dd459f9)

The actual response I am receiving in my case.
{
  "payload": {
    "OrderItems": [
      {
        "ASIN": "B09R3Q4J7K",
        "SellerSKU": "CORIA-SEE-WHO-ROM_1KG",
        "OrderItemId": "36448029324082",
        "Title": "Mimea Coriander Seeds Whole | 1kg | Quality Ingredients | Natural | No Additives | Great for Cooking | Fragrant Seasoning",
        "QuantityOrdered": 1,
        "QuantityShipped": 1,
        "ProductInfo": {
          "NumberOfItems": 1
        },
        "ItemPrice": {
          "CurrencyCode": "GBP",
          "Amount": "9.42"
        },
        "ShippingPrice": {
          "CurrencyCode": "GBP",
          "Amount": "0.61"
        },
        "ItemTax": {
          "CurrencyCode": "GBP",
          "Amount": "0.45"
        },
        "ShippingTax": {
          "CurrencyCode": "GBP",
          "Amount": "0.00"
        },
        "ShippingDiscount": {
          "CurrencyCode": "GBP",
          "Amount": "0.61"
        },
        "ShippingDiscountTax": {
          "CurrencyCode": "GBP",
          "Amount": "0.00"
        },
        "PromotionDiscount": {
          "CurrencyCode": "GBP",
          "Amount": "0.00"
        },
        "PromotionDiscountTax": {
          "CurrencyCode": "GBP",
          "Amount": "0.00"
        },
        "PromotionIds": [
          "PAWS-V2-22886240117-91"
        ],
        "IsGift": false,
        "IsTransparency": false,
        "BuyerInfo": {}
      }
    ],
    "AmazonOrderId": "205-15

[jlevers]

I'm no longer maintaining v5, so I recommend upgrading to v6. If you'd like to submit a PR to the v5.0 branch to fix this, I'm happy to merge it.