rename ahead_stopped -> side_stopped

Signed-off-by: Kento Yabuuchi <kento.yabuuchi.2@tier4.jp>

Author: KYabuuchi

autoware_launch/config/planning/scenario_planning/lane_driving/motion_planning/motion_velocity_planner/obstacle_cruise.param.yaml

@@ -96,7 +96,7 @@
             pedestrian: false
 
           # If an object does not have this label, the ego vehicle does not assume that the yielded obstacle will cut in due to the object.
-          ahead_stopped:
+          side_stopped:
             unknown: false
             car: true
             truck: true