test: fix test_command_output (#290)
test: fix test_command_output (#290)

1. The `with_setup` decorator does not appear to be designed to be used
   without parenthesis.  Remove it, since it is not needed/used anyway.
2. Fix the actual test.
zchee/python-client,meitham/python-client,neovim/python-client,Shougo/python-client,neovim/python-client,Shougo/python-client,zchee/python-client,meitham/python-client