Planning: treat signal and stop-sign equally in side-pass.

modules/planning/tasks/deciders/path_lane_borrow_decider/path_lane_borrow_decider.cc

@@ -147,6 +147,7 @@ bool PathLaneBorrowDecider::IsBlockingObstacleFarFromIntersection(
   // Get blocking obstacle's s.
   double blocking_obstacle_s =
       blocking_obstacle->PerceptionSLBoundary().end_s();
+  ADEBUG << "Blocking obstacle is at s = " << blocking_obstacle_s;
   // Get intersection's s and compare with threshold.
   const auto& first_encountered_overlaps =
       reference_line_info.FirstEncounteredOverlaps();
@@ -161,7 +162,8 @@ bool PathLaneBorrowDecider::IsBlockingObstacleFarFromIntersection(
     }
 
     auto distance = overlap.second.start_s - blocking_obstacle_s;
-    if (overlap.first == ReferenceLineInfo::SIGNAL) {
+    if (overlap.first == ReferenceLineInfo::SIGNAL ||
+        overlap.first == ReferenceLineInfo::STOP_SIGN) {
       if (distance < kIntersectionClearanceDist) {
         ADEBUG << "Too close to signal intersection (" << distance
                << "m); don't SIDE_PASS.";