Make `parse_date` return date rather than datetime
Make `parse_date` return date rather than datetime

This is only used in frontend.views.views and in every case we want a
date rather than a datetime.

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