fix(behavior_path_planner): fix redundantAssignment warning

[veqcc]

Description

This is a fix based on cppcheck redundantAssignment warning

planning/behavior_path_planner/autoware_behavior_path_planner_common/test/test_turn_signal.cpp:341:44: style: Variable 'behavior_signal_info.turn_signal.command' is reassigned a value before the old one has been used. [redundantAssignment]
  behavior_signal_info.turn_signal.command = TurnIndicatorsCommand::ENABLE_RIGHT;
                                           ^
planning/behavior_path_planner/autoware_behavior_path_planner_common/test/test_turn_signal.cpp:340:44: note: behavior_signal_info.turn_signal.command is assigned
  behavior_signal_info.turn_signal.command = TurnIndicatorsCommand::ENABLE_RIGHT;
                                           ^
planning/behavior_path_planner/autoware_behavior_path_planner_common/test/test_turn_signal.cpp:341:44: note: behavior_signal_info.turn_signal.command is overwritten
  behavior_signal_info.turn_signal.command = TurnIndicatorsCommand::ENABLE_RIGHT;
                                           ^

Tests performed

Not applicable.

Effects on system behavior

Not applicable.

Interface changes

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 13.11%. Comparing base (507e3f4) to head (c4ff758).
Report is 40 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7560      +/-   ##
==========================================
- Coverage   14.84%   13.11%   -1.74%     
==========================================
  Files        1999      524    -1475     
  Lines      139163    48672   -90491     
  Branches    43716    11793   -31923     
==========================================
- Hits        20661     6381   -14280     
+ Misses      95731    41348   -54383     
+ Partials    22771      943   -21828     

Flag	Coverage Δ
differential	13.11% <ø> (?)
total	?

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