A reporter at a Massachusetts-based newspaper resigned Friday after falsely claiming in a tweet Thursday that the man who killed five employees at the Capital Gazzete newspaper left a “Make America Great Again” hat at the crime scene. “Shooter who killed 4 people at Annapolis newspaper dropped his #MAGA hat on newsroom floor before opening fire,” Conor Berry, a reporter at The Republican in Springfield, Mass., wrote in a now-deleted tweet. Berry, who covered politics and crime for The Republican, apologized for the “stupid” and “regrettable” tweet Friday, adding that it made his 21-year career as a journalist come to...