Update ObstacleDetectionSensor.cpp

Change 100.0 to 100.0f as requested by bernatx in Pull Request #2182 from the carla master branch.

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Sensor/ObstacleDetectionSensor.cpp

@@ -139,6 +139,6 @@ void AObstacleDetectionSensor::OnObstacleDetectionEvent(
     GetDataStream(*this).Send(*this,
         Episode.SerializeActor(Episode.FindOrFakeActor(Actor)),
         Episode.SerializeActor(Episode.FindOrFakeActor(OtherActor)),
-        HitDistance/100.0);
+        HitDistance/100.0f);
   }
 }