Unskip middleware tests with Python 3. (#10884)
Unskip middleware tests with Python 3. (#10884)

Unskip middleware tests with Python 3.

Tested on a fresh project under Python 2 and 3, the behaviour difference
is coming from Django itself. This shouldn't be a problem in real-world
situations though, as browsers urlencode URLs when they make a request.
mozilla/addons-server,kumar303/addons-server,eviljeff/olympia,mozilla/olympia,psiinon/addons-server,kumar303/olympia,kumar303/olympia,kumar303/olympia,bqbn/addons-server,mozilla/addons-server,psiinon/addons-server,bqbn/addons-server,wagnerand/addons-server,mozilla/addons-server,eviljeff/olympia,mozilla/olympia,eviljeff/olympia,diox/olympia,wagnerand/addons-server,kumar303/addons-server,mozilla/olympia,diox/olympia,kumar303/addons-server,bqbn/addons-server,bqbn/addons-server,kumar303/olympia,mozilla/olympia,kumar303/addons-server,wagnerand/addons-server,wagnerand/addons-server,diox/olympia,mozilla/addons-server,psiinon/addons-server,eviljeff/olympia,diox/olympia,psiinon/addons-server