fix CI build + run tests on right postgres version
fix CI build + run tests on right postgres version

chris48s/UK-Polling-Stations,DemocracyClub/UK-Polling-Stations,chris48s/UK-Polling-Stations,DemocracyClub/UK-Polling-Stations,DemocracyClub/UK-Polling-Stations,chris48s/UK-Polling-Stations