By Andrew Chung WASHINGTON (Reuters) – The U.S. Supreme Court on Tuesday sided with an unsuccessful Republican candidate for a judgeship in Pennsylvania and threw out a lower court’s ruling that had allowed the counting of mail-in ballots in the race that he had sought to exclude because voters neglected to write the date on them. The justices vacated the ruling by the Philadelphia-based 3rd U.S. Circuit Court of Appeals as requested by David Ritter, who lost his 2021 bid for a spot on the Lehigh County Court of Common Pleas to a Democratic rival by five votes after 257 absentee ballots withou…