fix(lane_change): use previous module turn signal in waiting approval

[satoshi-ota]

Description

use previous module turn signal in waiting approval.

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[codecov]

Codecov Report

Patch coverage has no change and project coverage change: -0.01 ⚠️

Comparison is base (be0929b) 11.86% compared to head (be64c8e) 11.86%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3072      +/-   ##
==========================================
- Coverage   11.86%   11.86%   -0.01%     
==========================================
  Files        1333     1333              
  Lines       92801    92808       +7     
  Branches    24660    24666       +6     
==========================================
  Hits        11014    11014              
- Misses      70372    70379       +7     
  Partials    11415    11415              

Flag	Coverage Δ		*Carryforward flag
differential	5.54% <0.00%> (?)
total	11.86% <ø> (+<0.01%)	⬆️	Carriedforward from be0929b

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

Impacted Files	Coverage Δ
...lanner/include/behavior_path_planner/utilities.hpp	23.80% <ø> (ø)
...er/src/scene_module/avoidance/avoidance_module.cpp	0.00% <0.00%> (ø)
...rc/scene_module/lane_change/lane_change_module.cpp	0.00% <0.00%> (ø)
...ehavior_path_planner/src/util/lane_change/util.cpp	0.00% <0.00%> (ø)
planning/behavior_path_planner/src/utilities.cpp	7.52% <0.00%> (-0.05%)	⬇️

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[zulfaqar-azmi-t4]

LGTM