feat(traffic_light_fine_detector): add const in util function

[Shin-kyoto]

Description

• Add const in util function.

Tests performed

Not applicable.

Effects on system behavior

Not applicable.

Interface changes

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[codecov]

Codecov Report

Attention: Patch coverage is 0% with 6 lines in your changes missing coverage. Please review.

Project coverage is 0.00%. Comparing base (3d849e9) to head (982eee4).
Report is 534 commits behind head on main.

Files	Patch %	Lines
...eption/traffic_light_fine_detector/src/nodelet.cpp	0.00%	6 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #7172       +/-   ##
==========================================
- Coverage   15.09%   0.00%   -15.10%     
==========================================
  Files        1967      71     -1896     
  Lines      135941    4672   -131269     
  Branches    42122     471    -41651     
==========================================
- Hits        20520       0    -20520     
+ Misses      92700    4672    -88028     
+ Partials    22721       0    -22721     

Flag	Coverage Δ
differential	0.00% <0.00%> (?)
total	?

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