refactor(autoware_multi_object_tracker): merge normal_vehicle_tracker and big_vehicle_tracker

[technolojin]

Description

The normal_vehicle_tracker and big_vehicle_tracker has only difference of considering object size.
To remove redundant code, those are merged into one type vehicle_tracker.

This PR do not include any logic change.

Related links

Parent Issue:

• Link

How was this PR tested?

TIER IV INTERNAL

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 17 lines in your changes missing coverage. Please review.

Project coverage is 29.53%. Comparing base (01944ef) to head (a0e62d8).
Report is 6 commits behind head on main.

Files with missing lines	Patch %	Lines
...ject_tracker/lib/tracker/model/vehicle_tracker.cpp	0.00%	10 Missing ⚠️
...e_multi_object_tracker/src/processor/processor.cpp	0.00%	4 Missing ⚠️
...ker/lib/tracker/model/multiple_vehicle_tracker.cpp	0.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #9613      +/-   ##
==========================================
- Coverage   29.57%   29.53%   -0.05%     
==========================================
  Files        1442     1443       +1     
  Lines      108498   108651     +153     
  Branches    41396    41413      +17     
==========================================
  Hits        32092    32092              
- Misses      73285    73438     +153     
  Partials     3121     3121              

Flag	Coverage Δ		*Carryforward flag
differential	0.00% <0.00%> (?)
total	29.58% <ø> (+<0.01%)	⬆️	Carriedforward from 01944ef

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

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[yukkysaito]

@YoshiRi The change itself looks good, but I haven’t been able to check the coding style or detailed logic. Could I ask you to review those?

[YoshiRi]

I got it. Now tracker parameters are handled within object_model and vehicle tracker need only that information to switch its mode between large and normal vehicle.

LGTM