Test settings which don't depend on local ones
Test settings which don't depend on local ones

By overriding local settings we were cargo-culting things we didn't
want. Prefer explicit settings (still using the `base.py` environment as
a starting point)

ebmdatalab/openprescribing,annapowellsmith/openpresc,ebmdatalab/openprescribing,annapowellsmith/openpresc,annapowellsmith/openpresc,ebmdatalab/openprescribing,annapowellsmith/openpresc,ebmdatalab/openprescribing