Remove date handling function
Remove date handling function

We never call the bubble endpoint without supplying a date so there's no
need to support this.

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