fix(intersection): fix dying node

[takayuki5168]

Description

Without this PR, in some cases, the intersection module dies due to nullpointer access.

Tests performed

planning simulator

Effects on system behavior

Nothing

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[codecov]

Codecov Report

Patch and project coverage have no change.

Comparison is base (c8a889e) 14.07% compared to head (fe9407a) 14.07%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3555   +/-   ##
=======================================
  Coverage   14.07%   14.07%           
=======================================
  Files        1398     1398           
  Lines       97964    97962    -2     
  Branches    29084    29085    +1     
=======================================
  Hits        13790    13790           
+ Misses      69502    69500    -2     
  Partials    14672    14672           

Flag	Coverage Δ		*Carryforward flag
differential	3.45% <0.00%> (?)
total	14.07% <ø> (+<0.01%)	⬆️	Carriedforward from c8a889e

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

Impacted Files	Coverage Δ
...ier4_planning_rviz_plugin/include/path/display.hpp	0.00% <ø> (ø)
...c/scene_module/intersection/scene_intersection.cpp	0.00% <0.00%> (ø)

... and 1 file with indirect coverage changes

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