LONDON (Reuters) – A heat-wave prompted British shoppers to spend more on summer clothes, food for picnics and air conditioning units in July but they also cut back on foreign travel and dining out as the cost-of-living squeeze tightened, surveys showed on Tuesday. The British Retail Consortium said the value of total sales at its members – mostly large chains and major supermarkets – was 2.3% higher than in July 2021, a contrast with falls in each of the previous three months. Like-for-like sales, which adjusts for changes in floor space and shops closed due to lockdown restrictions, rose 1.6…