Mexico has overtaken the U.S. as the second largest importer of Brazil's beef after the imposition of tariffs by President Donald Trump on August 6 affected shipments from the world's largest exporter, Brazilian beef lobby Abiec said on Wednesday.Brazilian beef, which was already subject to a U.S. import tax of 26.4% outside of an exempt quota, now faces an additional 50% levy.Between August 1-25, Brazil exported 10…