Fix -Wunused-result of rcutils_logging

[christophfroehlich]

Starting >>> control_toolbox
--- stderr: control_toolbox                              
/workspaces/ros2_jazzy_ws/src/control_toolbox/control_toolbox/test/pid_ros_parameters_tests.cpp: In member function ‘virtual void PidParametersTest_PrintValuesLogsExpectedContent_Test::TestBody()’:
/workspaces/ros2_jazzy_ws/src/control_toolbox/control_toolbox/test/pid_ros_parameters_tests.cpp:763:35: warning: ignoring return value of ‘rcutils_ret_t rcutils_logging_set_logger_level(const char*, int)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
  763 |   rcutils_logging_set_logger_level(kLoggerName, RCUTILS_LOG_SEVERITY_INFO);
      |   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
---

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.35%. Comparing base (c0cdb15) to head (3de8076).

Additional details and impacted files

@@             Coverage Diff              @@
##           ros2-master     #506   +/-   ##
============================================
  Coverage        82.35%   82.35%           
============================================
  Files               29       29           
  Lines             1984     1984           
  Branches           114      114           
============================================
  Hits              1634     1634           
  Misses             281      281           
  Partials            69       69           

Flag	Coverage Δ
unittests	82.35% <100.00%> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
control_toolbox/test/pid_ros_parameters_tests.cpp	99.00% <100.00%> (ø)

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