checkLaneIsInIntersection function caused no lane following trajectory to be generated during lane change

[zulfaqar-azmi-t4]

Checklist

• I've read the contribution guidelines.
• I've searched other issues and no duplicate issues were found.
• I'm convinced that this is not my fault but a bug.

Description

During lane change, no lane following path is generated.

Expected behavior

If the distance is sufficient, a lane following trajectory should also be visualize

Actual behavior

The should be two path generated in this case, the first is the lane following trajectory, and another is the candidate path.

Steps to reproduce

1. Run autoware
2. Select start and end pose. Then end pose should be a lane change and should not place after intersection.

Versions

• OS: Ubuntu 20.04
• ROS: Galactic
• Autoware: Universe

Possible causes

To check for an intersection, checkLaneIsInIntersection requires at least two lanelets in the lane sequence.

However, the lane sequence size check only look for empty and not size == 1

bool checkLaneIsInIntersection(
  const RouteHandler & route_handler, const PathWithLaneId & reference_path,
  const lanelet::ConstLanelets & lanelet_sequence, double & additional_length_to_add)
{
  if (lanelet_sequence.empty()) {
    return false;
  }

 .......
}

Additional context

No response