Prime Minister Theresa May recently pledged that she would put an end to plastic by 2042 in a bid to tackle the waste problem here in Britain. Iceland is one supermarket that is already preparing to make the appropriate changes to get rid of plastic from their branded products — with an aim of doing so before 2023 after 80% of their customers said they would support the change. But where do supermarkets stand on the greater issue of food waste?…