SPRINGFIELD — The case that set the table for a high court battle over union fees could be headed back to the nation’s top justices.After winning at the U.S. Supreme Court a few years ago in the case of Harris v. Quinn, the same group of home-care workers is now asking the court to grant them a mass refund of payments deemed unconstitutional.Workers this week asked the nation’s top court to rule they’re eligible to recover about $32 million in fees they were required to pay between April 2008 and …