LONDON—British supermarket group Morrisons, at the centre of a bid battle between two U.S. private equity firms, on Thursday reported a 37.1 percent fall in first-half profit, hurt by COVID-19 costs and lost profit in cafes, fuel and food-to-go areas. The group, which trails market leader Tesco, Sainsbury’s and Asda in annual revenue, maintained its full-year guidance but warned of some industry-wide retail price inflation during the second half, driven by sustained commodity price increases and freight inflation, and the current shortage of HGV drivers. In a results statement that looks likely to be Bradford, northern England-based Morrisons’ last as a publicly listed company, it reported profit before tax and exceptional items of 105 million pounds ($144.5 million) in the six months to Aug. 1, down from 167 million pounds in the same period last year. Morrisons, which trades from 497 stores and has a staff of over 110,000, said …