feat(lane_change): improve the calculation of the target lateral velocity in Frenet frame

[maxime-clem]

Description

This PR makes the lane change paths generated in Frenet frame smoother.
The previous calculation did not work as expected, and the new calculation simply assumes a constant acceleration over the whole lane change duration, starting from a 0 lateral velocity and targeting some positive lateral velocity calculated as the lateral distance to travel divided by the lane change duration.

Before	After

Related links

Parent Issue:

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How was this PR tested?

Notes for reviewers

None.

Interface changes

None.

Effects on system behavior

None.

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[codecov]

Codecov Report

Attention: Patch coverage is 0% with 5 lines in your changes missing coverage. Please review.

Project coverage is 28.30%. Comparing base (421d9ec) to head (892b526).

Files with missing lines	Patch %	Lines
...ehavior_path_lane_change_module/src/utils/path.cpp	0.00%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #10078      +/-   ##
==========================================
- Coverage   28.30%   28.30%   -0.01%     
==========================================
  Files        1485     1486       +1     
  Lines      111091   111118      +27     
  Branches    43152    43154       +2     
==========================================
+ Hits        31445    31448       +3     
- Misses      76626    76651      +25     
+ Partials     3020     3019       -1     

Flag	Coverage Δ		*Carryforward flag
differential	21.04% <0.00%> (?)
total	28.30% <ø> (+<0.01%)	⬆️	Carriedforward from 421d9ec

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