Add new release repositories: etsi_its_messages

[lreiher]

Two of our ROS release repositories have just been moved to ros2-gbp, see here and here. I'd like to move a third release repository to ros2-gbp.

Also, one question: since the release repositories in here are only used for ROS2, am I right to assume that we should still keep releasing ROS1 updates to those repositories to the existing release repositories in our organization?

• Name of the release team: ika_rwth_aachen_team

• Release repositories to add:

  • ika-rwth-aachen/etsi_its_messages
  • ros/rosdistro source entry
  • [ ] There is an existing release repository which should be imported: ika-rwth-aachen/etsi_its_messages-release

[nuclearsandwich]

This change has been deployed!