fix(lane_change): add guard to neigibor lanelets

[kosuke55]

Description

Tests performed

Not applicable.

Effects on system behavior

Not applicable.

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[codecov]

Codecov Report

Attention: 3 lines in your changes are missing coverage. Please review.

Comparison is base (e12817d) 14.78% compared to head (be685e7) 14.78%.
Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #5245   +/-   ##
=======================================
  Coverage   14.78%   14.78%           
=======================================
  Files        1648     1648           
  Lines      113963   113947   -16     
  Branches    35110    35099   -11     
=======================================
  Hits        16848    16848           
+ Misses      78177    78164   -13     
+ Partials    18938    18935    -3     

Flag	Coverage Δ		*Carryforward flag
differential	12.43% <0.00%> (?)
total	14.78% <ø> (+<0.01%)	⬆️	Carriedforward from e12817d

*This pull request uses carry forward flags. Click here to find out more.

Files	Coverage Δ
...avior_velocity_intersection_module/src/manager.cpp	16.31% <ø> (ø)
...ity_intersection_module/src/scene_intersection.cpp	0.00% <ø> (ø)
...ity_intersection_module/src/scene_intersection.hpp	0.00% <ø> (ø)
...include/obstacle_cruise_planner/common_structs.hpp	8.69% <ø> (+0.09%)	⬆️
...lude/obstacle_cruise_planner/planner_interface.hpp	21.21% <ø> (+3.26%)	⬆️
planning/obstacle_cruise_planner/src/node.cpp	12.42% <ø> (+0.01%)	⬆️
.../obstacle_cruise_planner/src/planner_interface.cpp	6.21% <ø> (+0.01%)	⬆️
...th_planner/src/scene_module/lane_change/normal.cpp	4.46% <0.00%> (-0.01%)	⬇️
...avior_path_planner/src/utils/lane_change/utils.cpp	0.44% <0.00%> (-0.01%)	⬇️

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