nav2_costmap_2d: add missing default_value_ copy in Costmap2D operator=#4753

SteveMacenski merged 1 commit intoros-navigation:mainros-navigation/navigation2:mainfrom

DylanDeCoeyer-Quimesis:copy_costmap_2d_default_valueDylanDeCoeyer-Quimesis/navigation2:copy_costmap_2d_default_valueCopy head branch name to clipboard