Update readme

Author: moonbox3

python/samples/concepts/README.md

@@ -16,6 +16,7 @@
 - [Azure AI Agent Message Callback](./agents/azure_ai_agent/azure_ai_agent_message_callback.py)
 - [Azure AI Agent Streaming](./agents/azure_ai_agent/azure_ai_agent_streaming.py)
 - [Azure AI Agent Structured Outputs](./agents/azure_ai_agent/azure_ai_agent_structured_outputs.py)
+- [Azure AI Agent Truncation Strategy](./agents/azure_ai_agent/azure_ai_agent_truncation_strategy.py)
 
 #### [Bedrock Agent](../../semantic_kernel/agents/bedrock/bedrock_agent.py)