Drop elasticsearch index before i18n search tests
Drop elasticsearch index before i18n search tests

This should prevent errors like

Error: MapperParsingException[failed to parse [name]]; nested:
ElasticSearchIllegalArgumentException[unknown property [en]];

I've also added a 5s timeout to the whole describe block to hopefully
stop random failures.

mysociety/popit-api,mysociety/popit-api,Sinar/popit-api,Sinar/popit-api