fix: Update max_turns config (#12604)

Pass max_turns in the run config than during the initialization.

---------

Co-authored-by: Shivam Mishra <scm.mymail@gmail.com>

spec/enterprise/services/captain/assistant/agent_runner_service_spec.rb

@@ -90,7 +90,8 @@ RSpec.describe Captain::Assistant::AgentRunnerService do
 
       expect(mock_runner).to receive(:run).with(
         'I need help with my account',
-        context: expected_context
+        context: expected_context,
+        max_turns: 100
       )
 
       service.generate_response(message_history: message_history)