fix(autoware_control_validator): fix clang-diagnostic-unused-private-field

[veqcc]

Description

Removed unnecessary is_velocity_valid_ variable.

This solves the following clang-tidy error

autoware/src/universe/autoware.universe/control/autoware_control_validator/include/autoware/control_validator/control_validator.hpp:152:8: error: private field 'is_velocity_valid_' is not used [clang-diagnostic-unused-private-field]
  bool is_velocity_valid_{true};
       ^

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.

[github-actions]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 29.78%. Comparing base (a0c4ab4) to head (580dbb5).
Report is 27 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #9381      +/-   ##
==========================================
- Coverage   29.79%   29.78%   -0.01%     
==========================================
  Files        1338     1339       +1     
  Lines      103211   103229      +18     
  Branches    40212    40213       +1     
==========================================
  Hits        30748    30748              
- Misses      69477    69495      +18     
  Partials     2986     2986              

Flag	Coverage Δ		*Carryforward flag
differential	5.67% <ø> (?)
total	29.79% <ø> (ø)		Carriedforward from a0c4ab4

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[kyoichi-sugahara]

Thank you.LGTM