fix(samples): use valid agent name (underscores) in resilient_agent.py

Author: agent

samples/resilient_agent.py

@@ -51,7 +51,7 @@ async def generate_content_async(self, llm_request: LlmRequest, stream: bool = F
 
 async def main():
   # Agent with the failing-then-succeed model
-  agent = LlmAgent(name="resilient-agent", model="demo-fail-succeed")
+  agent = LlmAgent(name="resilient_agent", model="demo-fail-succeed")
 
   # Build services and runner in-memory
   artifact_service = InMemoryArtifactService()