Update release notes with banner accessibility enhancement

Author: rachelmcr

RELEASE-NOTES.txt

@@ -6,6 +6,7 @@
 - [*] Share payment links from the order details screen. [https://github.com/woocommerce/woocommerce-ios/pull/6609]
 - [internal] Reviews lists on Products and Menu tabs are refactored to avoid duplicated code. Please quickly smoke test them to make sure that everything still works as before. [https://github.com/woocommerce/woocommerce-ios/pull/6553]
 - [**] Now it's possible to change the order of the product images. [https://github.com/woocommerce/woocommerce-ios/pull/6620]
+- [*] Improved accessibility for the error banner and info banner displayed in Orders and Products. [https://github.com/woocommerce/woocommerce-ios/pull/6633]
 
 8.9
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