Fix: Add Tunnel features to error collector

CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/CityDoctorController.java

@@ -1222,6 +1222,7 @@ public class CityDoctorController {
         addErrorStats(stats, model.getBridges());
         addErrorStats(stats, model.getBuildings());
         addErrorStats(stats, model.getLand());
+        addErrorStats(stats, model.getTunnels());
         addErrorStats(stats, model.getTransportation());
         addErrorStats(stats, model.getVegetation());
         addErrorStats(stats, model.getWater());