U.S. District Judge Charles P. Kocoras might have been sitting on a beach last week instead of in a federal courtroom if he had accepted a business proposition after earning his bachelor’s degree.Kocoras had worked in a liquor store while going to school.The owner — “who was as marvelous a human being as you can imagine” — offered him a partnership in the store and his other business ventures, Kocoras said at an event Thursday at the Dirksen Federal Courthouse.But he declined the offer, he …