tests: Add ability to test different expected outputs based on Python version. Similar to the previous change, there was also a change in what gets escaped by `urllib.parse.quote` (as in: the tilde sign ('~') stopped being escaped). So now we need to be able to test different outputs in the tests, yay again.

import os
from invoke import task, run


@task
def genmessages(ctx):
    root_dir = 'garcon/messages'
    out_dir = 'piecrust/resources/messages'
    run('python chef.py --root %s bake -o %s' % (root_dir, out_dir))
    os.unlink('piecrust/resources/messages/index.html')