Revert "Remap the diagnostics topic too"

This reverts commit 8b9a9a7.

Author: civerachb-cpr

turtlebot4_navigation/launch/slam.launch.py

@@ -88,7 +88,6 @@ def launch_setup(context, *args, **kwargs):
 
         SetRemap('/tf', namespace_str + '/tf'),
         SetRemap('/tf_static', namespace_str + '/tf_static'),
-        SetRemap('/diagnostics', namespace_str + '/diagnostics'),
 
         IncludeLaunchDescription(
             PythonLaunchDescriptionSource(launch_slam_sync),