fix: fix doc string typo (#560)

Author: h4ck3rk3y

main.star

@@ -55,7 +55,7 @@ def run(plan, args={}):
     """Launches an arbitrarily complex ethereum testnet based on the arguments provided
 
     Args:
-        arg: A YAML or JSON argument to configure the network; example https://github.com/kurtosis-tech/ethereum-package/blob/main/network_params.yaml
+        args: A YAML or JSON argument to configure the network; example https://github.com/kurtosis-tech/ethereum-package/blob/main/network_params.yaml
     """
 
     args_with_right_defaults = input_parser.input_parser(plan, args)