Fix CHANGELOG structure: drop empty top-level sections, follow module-section pattern

Agent-Logs-Url: https://github.com/Azure/azure-sdk-for-java/sessions/59374aea-7b8d-4f93-8ead-643620e36c89

Co-authored-by: rujche <171773178+rujche@users.noreply.github.com>

Author: Copilot

sdk/spring/CHANGELOG.md

@@ -1,12 +1,6 @@
 # Release History
 ## 7.3.0-beta.1 (Unreleased)
 
-### Features Added
-
-### Breaking Changes
-
-### Bugs Fixed
-
 ### Spring Cloud Azure Autoconfigure
 
 This section includes changes in `spring-cloud-azure-autoconfigure` module.
@@ -15,8 +9,6 @@ This section includes changes in `spring-cloud-azure-autoconfigure` module.
 
 - Fixed `azure.scopes` using wrong default value for Azure China and Azure US Government when `spring.cloud.azure.profile.cloud-type` is set to `azure_china` or `azure_us_government`. The scopes are now correctly derived from the merged cloud type. ([#47096](https://github.com/Azure/azure-sdk-for-java/issues/47096))
 
-### Other Changes
-
 ## 7.2.0 (2026-04-17)
 - This release is compatible with Spring Boot 4.0.0-4.0.5. (Note: 4.0.x (x>5) should be supported, but they aren't tested with this release.)
 - This release is compatible with Spring Cloud 2025.1.0-2025.1.1. (Note: 2025.1.x (x>1) should be supported, but they aren't tested with this release.)