Revert "Use transactional strategy for database cleaner"
Revert "Use transactional strategy for database cleaner"

Wrapping each test in a transaction is bad because it means we cannot
test transactions within individual app requests.

askl56/whitehall,YOTOV-LIMITED/whitehall,hotvulcan/whitehall,robinwhittleton/whitehall,robinwhittleton/whitehall,ggoral/whitehall,askl56/whitehall,alphagov/whitehall,YOTOV-LIMITED/whitehall,askl56/whitehall,robinwhittleton/whitehall,ggoral/whitehall,YOTOV-LIMITED/whitehall,ggoral/whitehall,robinwhittleton/whitehall,hotvulcan/whitehall,hotvulcan/whitehall,alphagov/whitehall,ggoral/whitehall,hotvulcan/whitehall,alphagov/whitehall,YOTOV-LIMITED/whitehall,alphagov/whitehall,askl56/whitehall