Update release notes

Author: itsmeichigo

RELEASE-NOTES.txt

@@ -6,6 +6,7 @@
 - [*] Shipping Labels: Improve UI of Split shipments screen. [https://github.com/woocommerce/woocommerce-ios/pull/15838]
 - [*] POS: icon button with confirmation step used for clearing the cart [https://github.com/woocommerce/woocommerce-ios/pull/15829]
 - [*] Shipping Labels: Fixed a portion of layout issues caused by bigger accessibility content size categories. [https://github.com/woocommerce/woocommerce-ios/pull/15844]
+- [*] Shipping Labels: Enable the confirm button on the payment method sheet even when there are no changes. [https://github.com/woocommerce/woocommerce-ios/pull/15856]
 
 22.7
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