Update CHANGELOG.md

Author: lzchen

CHANGELOG.md

@@ -3,7 +3,7 @@
 ## Unreleased
 
 - Reverse default behavior of instrumentations and implement configuration for exclusion
-    ([#250](https://github.com/microsoft/ApplicationInsights-Python/pull/250))
+    ([#253](https://github.com/microsoft/ApplicationInsights-Python/pull/253))
 
 ## [1.0.0b10](https://github.com/microsoft/ApplicationInsights-Python/releases/tag/v1.0.0b10) - 2023-02-23