WIP: Port mir gazebo simulation to ros2 jazzy and Gazebo harmonic

[oscar-lima]

To test, use:

• ros2 launch mir_gazebo mir_gazebo_launch.py world:=maze
  or
• ros2 launch mir_gazebo mir_gazebo_launch.py world:=maze namespace:=my_robot_ns
  Make sure you have installed:
• https://github.com/relffok/ira_laser_tools (fork)

Features:

• ported mir_description as it was a dependency
• imu, joint states, gpu lidar, diff drive plugins ported (no ros2 gz control plugin was needed)
• gazebo bridge is setup, selected topics are exposed to ros2
• NOTE: join_states in gazebo is bridged as mir_joint_states in ros2, then jsp subscribes to it and adds caster states as 0.0
  this means: doing gz topic -l one will see /joint_states but /mir_joint_states on ros2 side, then jsp subscribes to /mir_joint_states and publishes /joint_states and /dynamic_joint_states

Missing:

• nav2, only bringup is ported for now, i.e.: joint states, tf, namespace works, lidar merger (basic functionality only)
• mir_empty_world.launch, mir_gazebo_common.launch not yet ported
• ekf/fake localization

Feedback is welcome.