Update release notes for order creation release

Author: rachelmcr

RELEASE-NOTES.txt

@@ -4,6 +4,7 @@
 -----
 - [*] Coupons: Fixed issue loading the coupon list from the local storage on initial load. [https://github.com/woocommerce/woocommerce-ios/pull/6463]
 - [*] Jetpack CP: Fixed crash when attempting to access WP-Admin with an invalid URL that has an unsupported scheme. [https://github.com/woocommerce/woocommerce-ios/pull/6502]
+- [***] Orders: Order Creation is now available to everyone! You can go to the Orders tab and tap the + button to create a new order. [https://github.com/woocommerce/woocommerce-ios/pull/6537]
 
 8.8
 -----