General Motors Co. on Friday said its dealers sold 512,846 vehicles in the first quarter this year, down 20% from last year as slumping supply continued to limit sales. Again, Toyota Motor North America surpassed GM’s sales with a total of 514,592 sales reported in the first quarter for a 14.7% year-over-year decline. Last year, Toyota dethroned GM as America’s top-selling automaker. The Japanese automaker outsold GM by more than 114,000 vehicles in 2021, with more than 2.3 million vehicles sold for the year. GM sold 2.2 million vehicles in 2021, dropping 13% from 2020 as the automaker battled…