Another edge case to return false where the update file cannot be written
Another edge case to return false where the update file cannot be written

This is so we dont create dangling pending entries in the tariff_updates table

leftees/trade-tariff-backend,alphagov/trade-tariff-backend,alphagov/trade-tariff-backend,leftees/trade-tariff-backend,bitzesty/trade-tariff-backend,alphagov/trade-tariff-backend,bitzesty/trade-tariff-backend,leftees/trade-tariff-backend,bitzesty/trade-tariff-backend