planning: fix lint error.

modules/planning/common/reference_line_info.cc

@@ -300,7 +300,7 @@ bool ReferenceLineInfo::AddObstacles(
     for (const auto* obstacle : obstacles) {
       results.push_back(task->Execute(std::make_shared<Obstacle>(*obstacle)));
     }
-    for (auto& result: results) {
+    for (auto& result : results) {
       result.get();
     }
   } else {

modules/planning/toolkits/optimizers/dp_st_speed/dp_st_graph.cc

@@ -196,7 +196,7 @@ Status DpStGraph::CalculateTotalCost() {
         }
       }
       if (FLAGS_enable_multi_thread_in_dp_st_graph) {
-        for (auto& result: results) {
+        for (auto& result : results) {
           result.get();
         }
       }

modules/planning/toolkits/optimizers/road_graph/dp_road_graph.cc

@@ -186,7 +186,7 @@ bool DpRoadGraph::GenerateMinCostPath(
       }
     }
     if (FLAGS_enable_multi_thread_in_dp_poly_path) {
-      for (auto& result: results) {
+      for (auto& result : results) {
         result.get();
       }
     }