WILLMAR — As with every year around the Fourth of July, physicians are once again urging Minnesotans to leave fireworks to the professionals over the holiday weekend this year. President Lisa Mattson, M.D., of the Minnesota Medical Association, said in a written statement, “every summer we hear of too many sad stories about people getting injured by fireworks. ... So please stay away from firecrackers, bottle rockets, Roman candles, sparklers an…