fix(obstacle_cruise_planner): fix stop against objects after backward trajectory terminal

[kosuke55]

Description

cherry-pick

• fix(obstacle_cruise_planner): fix stop against objects after backward trajectory terminal autowarefoundation/autoware.universe#5031
• fix(obstacle_cruise_planner): fix backward virtual wall autowarefoundation/autoware.universe#5028

Related links

Tests performed

psim in main

build in this branch

Notes for reviewers

none

Interface changes

none

Effects on system behavior

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