perf(autoware_map_based_prediction): replace pow

[TakaHoribe]

Description

A performance analysis of the map_based_prediction with VTune was performed. The generated frame graph is below.

For example, you see std::pow accounts for 50% of the generateFrenetPath function's processing time.

Replacing std::pow with a simple multiplier reduces the computation time of this function from 2.2 ms to 0.6 ms for 1000 calculations. This is the PR.
(The function is called for each combination of "the number of objects" and "the number of predicted paths".)

Related links

None

How was this PR tested?

• I visually confirmed that the prediction is working correctly in psim.

Notes for reviewers

None.

Interface changes

None.

Effects on system behavior

None.

[github-actions]

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[codecov]

Codecov Report

Attention: Patch coverage is 0% with 21 lines in your changes missing coverage. Please review.

Project coverage is 25.03%. Comparing base (757a5a5) to head (0331b26).
Report is 50 commits behind head on main.

Files with missing lines	Patch %	Lines
...toware_map_based_prediction/src/path_generator.cpp	0.00%	21 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8751      +/-   ##
==========================================
- Coverage   25.04%   25.03%   -0.02%     
==========================================
  Files        1315     1317       +2     
  Lines       97969    98009      +40     
  Branches    37804    37806       +2     
==========================================
  Hits        24536    24536              
- Misses      70923    70963      +40     
  Partials     2510     2510              

Flag	Coverage Δ		*Carryforward flag
differential	2.08% <0.00%> (?)
total	25.04% <ø> (+<0.01%)	⬆️	Carriedforward from 757a5a5

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[YoshiRi]

LGTM