refactor(ekf_localizer): add a warning class

[IshitaTakeshi]

Description

Add a warning class to simplify displaying messages

Related links

Tests performed

Tests need to be performed to validate the displayed messages, but they should be done in another PR.

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[codecov]

Codecov Report

Merging #1837 (a1f70c9) into main (cb2552b) will decrease coverage by 0.02%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main    #1837      +/-   ##
==========================================
- Coverage   10.44%   10.41%   -0.03%     
==========================================
  Files        1221     1222       +1     
  Lines       87728    87926     +198     
  Branches    20493    20653     +160     
==========================================
  Hits         9160     9160              
- Misses      69091    69274     +183     
- Partials     9477     9492      +15     

Flag	Coverage Δ		*Carryforward flag
differential	17.50% <0.00%> (?)
total	10.42% <0.00%> (ø)		Carriedforward from cb2552b

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

Impacted Files	Coverage Δ
..._localizer/include/ekf_localizer/ekf_localizer.hpp	0.00% <ø> (ø)
...on/ekf_localizer/include/ekf_localizer/warning.hpp	0.00% <0.00%> (ø)
localization/ekf_localizer/src/ekf_localizer.cpp	0.00% <0.00%> (ø)
...include/behavior_velocity_planner/planner_data.hpp	0.00% <0.00%> (ø)
planning/behavior_velocity_planner/src/node.cpp	0.42% <0.00%> (ø)

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[kminoda]

Would you mind explaining the aim of this PR more concretely?

I personally think that the original warnings using RCLCPP_WARNs is also not too bad.
The other packages also use the same warning formats for now, so I'd say it's better to leave it as it is as long as we don't have strong reason to change it as in this PR.

What do you think?

[IshitaTakeshi]

For people who read the code, for example, the line

    RCLCPP_WARN_THROTTLE(
      get_logger(), *get_clock(), std::chrono::milliseconds(1000).count(),
      "Twist delay exceeds the compensation limit, ignored. delay: %f[s], limit = "
      "extend_state_step * ekf_dt : %f [s]",
      delay_time, extend_state_step_ * ekf_dt_);

is too noisy. For readers, it is not necessary to know how to obtain the logger from the node and clock, i.e., get_logger and get_clock respectively, and it is not necessary to see how to represent the duration std::chrono::milliseconds(duration).count().

The basic strategy to improve readability and maintainability is to improve cohesion, and it is what I did here.

[kminoda]

LGTM!