Update the release date in CHANGELOG for 1.0.0b1 release (#35786)

Author: zihyunting

sdk/face/azure-ai-vision-face/CHANGELOG.md

@@ -1,6 +1,6 @@
 # Release History
 
-## 1.0.0b1 (Unreleased)
+## 1.0.0b1 (2024-05-28)
 
 This is the first preview of the `azure-ai-vision-face` client library that follows the [Azure Python SDK Design Guidelines](https://azure.github.io/azure-sdk/python_design.html).
 This library replaces the package [azure-cognitiveservices-vision-face](https://pypi.org/project/azure-cognitiveservices-vision-face/).