[NFC] Don't have null values for required fields in Case test fixture

[demeritcowboy]

Overview

The fields get created as NULL, which doesn't make sense for start_date, and at least on the form subject is required.

I don't think this is used much - tests generally create their own case - but this is more realistic data.

[civibot]

(Standard links)

• If you are reviewing this pull-request, you may wish to consult the test sites and the Review Standards (long template, short template).

[eileenmcnaughton]

Yeah it seems to be loaded in loadAllFixutres() so it is at least not unused