By Devik Jain and Sruthi Shankar (Reuters) -British stocks ended lower on Monday as data showed the economy slowed more than expected in February, intensifying worries about a cost-of-living squeeze. Gross domestic product rose by 0.1% in February, missing the 0.3% rise forecast by economists in a Reuters poll and down from a 0.8% increase in January. London’s leading share index closed 0.7% lower, pulling back from its strongest level in nearly two months, while the domestically focused FTSE 250 midcap index declined 0.3%. “The winding down of the UK’s booster vaccine and Covid-19 test campai…