Remove assertion in django_settings_is_configured
Remove assertion in django_settings_is_configured

django.conf.settings.configured is not necessarily True, in case DSM
wasn't set during `pytest_load_initial_conftests`, but gets set in the
project's conftest (via `pytest_configure`).

Fixes https://github.com/pytest-dev/pytest-django/issues/146

aptivate/pytest-django,ktosiek/pytest-django,pombredanne/pytest_django,felixonmars/pytest-django,bforchhammer/pytest-django,davidszotten/pytest-django,RonnyPfannschmidt/pytest_django,ojake/pytest-django,thedrow/pytest-django,reincubate/pytest-django,tomviner/pytest-django,pelme/pytest-django,hoh/pytest-django