Allow DJANGO_SETTINGS_MODULE to be customized in reviewboard.wsgi.
Review Request #13503 — Created Jan. 18, 2024 and updated
reviewboard.wsgimodule had hard-coded
reviewboard.settings. This is fine for 99.999% of users, but for some
very specialized cases, a separate settings module may need to be used.
In order to make this as easy as possible, any existing
DJANGO_SETTINGS_MODULEwill now be respected, rather than being
Tested this on an in-development server with a customized settings