Refactor rgbd_camera_bridge demo

[caguero]

Refactors the rgbd_camera_bridge demo leveraging the latest improvements in ros_gz.

• I replaced the previous launch file from Python to XML.
• I didn't tackle the options using ros_gz_image or ros_gz_point_cloud for now.

Summary

Checklist

• Signed all commits for DCO
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
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[ahcorde]

similar comment #634

[ahcorde]

Do you to add the Grid plugin to RViz?

[caguero]

Do you to add the Grid plugin to RViz?

Loaded in aebe372.

[caguero]

similar comment #634

This one is a bit tricker. The rgbd_camera sensor publishes on the ROS side:

- topic_name: "/rgbd_camera/image"
 ros_type_name: "sensor_msgs/msg/Image"
- topic_name: "/rgbd_camera/camera_info"
  ros_type_name: "sensor_msgs/msg/CameraInfo"
- topic_name: "/rgbd_camera/depth_image"
  ros_type_name: "sensor_msgs/msg/Image"
- topic_name: "/rgbd_camera/points"
  ros_type_name: "sensor_msgs/msg/PointCloud2"

All of these topics share the same frame_id, which is rgbd_camera/link/rgbd_camera. The problem is that the ROS/Gazebo coordinate convention is different for all these topics except for /rgbd_camera/points, which is correct.

The proper solution should be to republish /rgbd_camera/image, /rgbd_camera/camera_info and /rgbd_camera/depth_image with a different topic and also changing frame_id. We could then add a static_transform_publisher for the new frame_id with the transformation.

Alternatively, we could also try to resurrect #257 and combine it with some remappings similar to https://github.com/osrf/mbzirc/blob/main/mbzirc_ign/src/mbzirc_ign/model.py#L235-L260 (thanks @iche033 for the pointers).

I'd leave it for a separate PR.