feat(obstacle_curise): revert lateral stop margin for unknown objects (#1015)

Signed-off-by: Yuki Takagi <yuki.takagi@tier4.jp>

Author: yuki-takagi-66

autoware_launch/config/planning/scenario_planning/lane_driving/motion_planning/obstacle_cruise_planner/obstacle_cruise_planner.param.yaml

@@ -88,7 +88,7 @@
 
       stop:
         max_lat_margin: 0.3 # lateral margin between the obstacles and ego's footprint
-        max_lat_margin_against_unknown: -0.3 # lateral margin between the unknown obstacles and ego's footprint
+        max_lat_margin_against_unknown: 0.3 # lateral margin between the unknown obstacles and ego's footprint
         crossing_obstacle:
           collision_time_margin : 4.0 # time threshold of collision between obstacle adn ego for cruise or stop [s]