After more than 4200 submissions, the 12th annual NBCUniversal Short Film Festival announced the winners from a slate of nine finalists in the grand finale event in Los Angeles tonight. The competition was stiff as the nine short films and web series presented were amazingly crafted and thoughtful entries, but the two shorts that came out on top were Cynthia Kao’s Groundhog Day For A Black Man and Cullan Bruce’s Lost Dogs. Groundhog Day For A Black Man tells a hilarious…