Cannot return null for non-nullable field SelectedCustomizableOptionValue.sort_order and Call to a member function getPriceType() on null

Author: XxXgeoXxX

app/code/Magento/QuoteGraphQl/etc/schema.graphqls

@@ -325,7 +325,6 @@ type SelectedCustomizableOptionValue {
     label: String!
     value: String!
     price: CartItemSelectedOptionValuePrice!
-    sort_order: Int!
 }
 
 type CartItemSelectedOptionValuePrice {

dev/tests/api-functional/testsuite/Magento/GraphQl/CatalogInventory/AddProductToCartTest.php

@@ -52,7 +52,7 @@ public function testAddProductIfQuantityIsNotAvailable()
      * @expectedException \Exception
      * @expectedExceptionMessage The product's required option(s) weren't entered. Make sure the options are entered and try again.
      */
-    public function testAddProductWithoutRequiredCustomOPtions()
+    public function testAddProductWithoutRequiredCustomOptions()
     {
         $sku = 'simple_with_custom_options';
         $qty = 1;
@@ -66,7 +66,7 @@ public function testAddProductWithoutRequiredCustomOPtions()
      * @magentoApiDataFixture Magento/Catalog/_files/product_simple_with_custom_options.php
      * @magentoApiDataFixture Magento/Checkout/_files/active_quote.php
      */
-    public function testAddProductWithRequiredCustomOPtions()
+    public function testAddProductWithRequiredCustomOptions()
     {
         $sku = 'simple_with_custom_options';
         $qty = 1;