[Storage] Move release notes to Upcoming section

Co-authored-by: AustinBenoit <22805659+AustinBenoit@users.noreply.github.com>

Author: google-labs-jules[bot]

release_build_files/readme.md

@@ -613,9 +613,12 @@ workflow use only during the development of your app, not for publicly shipping
 code.
 
 ## Release Notes
-### 13.5.0
+### Upcoming
 -   Changes
     - Storage: Added `List` API across all platforms.
+
+### 13.5.0
+-   Changes
     - General (Android): Update to Firebase Android BoM version 34.10.0.
     - General (iOS): Update to Firebase Cocoapods version 12.10.0.
     - App Check: Add in support for Limited Use Tokens.