fix roundabout handling with lanes

instead of artificially removing lanes from a roundabout, we don't assing them in the first place.
this also prevents a problem where we would end up collapsing turns with lanes in a roundabout

src/extractor/guidance/intersection_handler.cpp

@@ -1,6 +1,7 @@
 #include "extractor/guidance/intersection_handler.hpp"
 #include "extractor/guidance/constants.hpp"
 
+#include "util/coordinate_calculation.hpp"
 #include "util/guidance/name_announcements.hpp"
 #include "util/log.hpp"