update changelog (#40262)

Author: xiangyan99

sdk/core/corehttp/CHANGELOG.md

@@ -1,6 +1,6 @@
 # Release History
 
-## 1.0.0b6 (Unreleased)
+## 1.0.0b6 (2025-03-27)
 
 ### Features Added
 
@@ -18,10 +18,6 @@
 - The `AccessToken` class has been removed and replaced with a new `AccessTokenInfo` class. [#38346](https://github.com/Azure/azure-sdk-for-python/pull/38346)
 - `BearerTokenCredentialPolicy` and `AsyncBearerTokenCredentialPolicy` now rely on credentials having the `get_token_info` method defined. [#38346](https://github.com/Azure/azure-sdk-for-python/pull/38346)
 
-### Bugs Fixed
-
-### Other Changes
-
 ## 1.0.0b5 (2024-02-29)
 
 ### Other Changes