Replace rclcpp::Rate with rclcpp::WallRate

[onionsflying]

Description

rclcpp::WallRate is preferable to rclcpp::Rate, because with rclcpp::WallRate rate.sleep() won’t stall due to backward system clock adjustments (e.g., a one-day rollback).

[mergify]

Please target the main branch for development, we will backport the changes to humble for you if approved and if they don't break API.

[codecov]

Codecov Report

❌ Patch coverage is 50.00000% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 50.95%. Comparing base (3f2d7f5) to head (e42e7f3).
⚠️ Report is 1 commits behind head on humble.

Files with missing lines	Patch %	Lines
...nitor/src/trajectory_monitor_middleware_handle.cpp	0.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           humble    #3557   +/-   ##
=======================================
  Coverage   50.95%   50.95%           
=======================================
  Files         390      390           
  Lines       32521    32521           
=======================================
  Hits        16567    16567           
  Misses      15954    15954           

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