Update the testing notes

Remove #5870 testing notes because they can't be tested as a user

Author: tarhi-saad

docs/testing/releases/740.md

@@ -75,12 +75,3 @@ Zip file for testing: [woocommerce-gutenberg-products-block.zip](https://github.
 
 1. Go to the shop page and add any product to the cart
 2. Go to the Cart block page and increase product quantity to 9999
-
-### Decode HTML entities when formatting Store API error messages. ([5870](https://github.com/woocommerce/woocommerce-gutenberg-products-block/pull/5870))
-
-1. Add a callback to the wooocommerce_store_api_validate_cart_item action and throw a RouteException that includes HTML entities.
-2. Open the Cart Block.
-3. You should see a notice with the message you added to your Exception.
-4. Go to the Checkout Block.
-5. Attempt to place the order.
-6. You should see the same message, with entities decoded.