feat(lane_change): consider deceleration in safety check for cancel (autowarefoundation#1068)

Signed-off-by: Fumiya Watanabe <rej55.g@gmail.com>

Author: rej55

autoware_launch/config/planning/scenario_planning/lane_driving/behavior_planning/behavior_path_planner/lane_change/lane_change.param.yaml

@@ -120,6 +120,7 @@
         max_lateral_jerk: 100.0             # [m/s3]
         overhang_tolerance: 0.0             # [m]
         unsafe_hysteresis_threshold: 5      # [/]
+        deceleration_sampling_num: 5 # [/]
 
       lane_change_finish_judge_buffer: 2.0      # [m]
       finish_judge_lateral_threshold: 0.1        # [m]