Reduce extraction distance to 120 meters

For intersection at https://www.openstreetmap.org/node/65299217
`are_parallel` in MergableRoadDetector::HaveSameDirection is false
for South Van Ness Avenue with 150 meters

include/extractor/guidance/mergable_road_detector.hpp

@@ -178,7 +178,7 @@ class MergableRoadDetector
     const CoordinateExtractor coordinate_extractor;
 
     // limit for detecting circles / parallel roads
-    const static double constexpr distance_to_extract = 150;
+    const static double constexpr distance_to_extract = 120;
 };
 
 } // namespace guidance