Fix broken link in examples documentation (#5427)

examples/extension/README.md

@@ -1,6 +1,6 @@
 ## Introduction
 
-Extensions add new features and capabilities to the agent without having to create a separate distribution (for examples and ideas, see [Use cases for extensions](#use-cases-for-extensions)). 
+Extensions add new features and capabilities to the agent without having to create a separate distribution (for examples and ideas, see [Use cases for extensions](#sample-use-cases)).
 
 The contents in this folder demonstrate how to create an extension for the OpenTelemetry Java instrumentation agent, with examples for every extension point.