add entry of readme in script

examples/android_assistant/run_assistant.py

@@ -2,6 +2,7 @@
 # -*- coding: utf-8 -*-
 # @Desc   : the entry of android assistant including learning and acting stage
 #           See the usage README inside `metagpt/ext/android_assistant`
+#           README see `metagpt/ext/android_assistant/README.md`
 
 import asyncio
 from pathlib import Path

examples/stanford_town/run_st_game.py

@@ -1,6 +1,7 @@
 #!/usr/bin/env python
 # -*- coding: utf-8 -*-
 # @Desc   : entry of Stanford Town(ST/st) game
+#           README see `metagpt/ext/stanford_town/README.md`
 
 import asyncio
 from typing import Optional