fix: include_thought set to false in case of missing run_config

Author: lorenzbaraldi

src/google/adk/flows/llm_flows/contents.py

@@ -67,8 +67,11 @@ async def run_async(
     # Preserve all contents that were added by instruction processor
     # (since llm_request.contents will be completely reassigned below)
     instruction_related_contents = llm_request.contents
+    run_config = invocation_context.run_config
     include_thoughts_from_other_agents = (
-        invocation_context.run_config.include_thoughts_from_other_agents
+        run_config.include_thoughts_from_other_agents
+        if run_config is not None
+        else False
     )
 
     if agent.include_contents == 'default':