avoid passing factory address (#11236)

op-challenger/README.md

@@ -154,7 +154,7 @@ If the game is resolved successfully, the result is printed.
 ```shell
 ./bin/op-challenger list-games \
   --l1-eth-rpc <L1_ETH_RPC> \
-  --game-factory-address <GAME_FACTORY_ADDRESS>
+  --network <Predefined_Network>
 ```
 
 Prints the games created by the game factory along with their current status.