refactor(control): remove unimplemented function declarations

[Autumn60]

Description

For LaneDepartureCheckerNode class,
In #7358 , the implementation of the callback function has been removed, but the declaration has not.

Related links

#7358

How was this PR tested?

Notes for reviewers

None.

Interface changes

None.

Effects on system behavior

None.

[github-actions]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 26.34%. Comparing base (63c5607) to head (0fbf54e).
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #10314      +/-   ##
==========================================
+ Coverage   25.94%   26.34%   +0.39%     
==========================================
  Files        1383     1387       +4     
  Lines      106833   107415     +582     
  Branches    40912    41006      +94     
==========================================
+ Hits        27722    28297     +575     
+ Misses      76403    76401       -2     
- Partials     2708     2717       +9     

Flag	Coverage Δ		*Carryforward flag
differential	26.48% <ø> (?)
total	25.92% <ø> (-0.03%)	⬇️	Carriedforward from dc44b22

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[kyoichi-sugahara]

Thank you! LGTM.