typo in "11_args.py"

[HakujouRyu]

The print statements starting on line 17 will print out "None" if the function "f2" is written as described in the instructions.
This change will make the comments next to the print statements accurate.

[HakujouRyu]

Proposed fix: https://github.com/LambdaSchool/Intro-Python-I/pull/704/files