Add 7.4 release notes

Author: jkmassel

WooCommerce/Resources/release_notes.txt

@@ -1,6 +1,3 @@
-- [*] Fix an issue where some extension was not shown in order item details. [https://github.com/woocommerce/woocommerce-ios/pull/4753]
-- [*] Fix: The refund button within Order Details will be hidden if the refund is zero. [https://github.com/woocommerce/woocommerce-ios/pull/4789]
-- [*] Fix: Incorrect arrow direction for right-to-left languages on Shipping Label flow. [https://github.com/woocommerce/woocommerce-ios/pull/4796]
-- [*] Fix: Shouldn't be able to schedule a sale without sale price. [https://github.com/woocommerce/woocommerce-ios/pull/4825]
-- [*] Fix: Edit address screen is pushed twice in Shipping Label flow when missing name in origin or destination address. [https://github.com/woocommerce/woocommerce-ios/pull/4845]
+This release contains a handful of minor improvements to make your experience smoother. In order details, some third-party extensions were not logically showing product metadata. We’ve made some changes to improve the display of those product details. We now are hiding the refund order button when the total amount is zero.
 
+This update also includes several enhancements to the shipping label feature using the WooCommerce Shipping & Tax Extension. We value all of your feedback on this newer feature!