Fix range_response test

[Archmonger]

Description

The range response test in test_django_servestatic was disabled due to bugs related to the test suite. It is assumed that the pytest fixture AppServer was conflicting with how Django provides WSGI range responses, resulting in an empty response.

It was manually tested that ServeStatic+Django do properly provide range responses under WSGI, so some effort will need to be made to fix this test.

If too complicated to fix, we can consider rewriting the tests to not use janky simulations and instead use real application instances and a Chromium browser window via playwright (see example).