fix: pointcloud_octomap_updater not cleaning objects at max_range (#3294

) (#3304)

(cherry picked from commit bb7463a)

Co-authored-by: Marco Magri <94347649+MarcoMagriDev@users.noreply.github.com>

moveit_ros/perception/pointcloud_octomap_updater/src/pointcloud_octomap_updater.cpp

@@ -338,6 +338,7 @@ void PointCloudOctomapUpdater::cloudMsgCallback(const sensor_msgs::msg::PointClo
     /* compute the free cells along each ray that ends at a clipped cell */
     for (const octomap::OcTreeKey& clip_cell : clip_cells)
     {
+      free_cells.insert(clip_cell);
       if (tree_->computeRayKeys(sensor_origin, tree_->keyToCoord(clip_cell), key_ray_))
         free_cells.insert(key_ray_.begin(), key_ray_.end());
     }