deleteCache deletes all stations related to taht cache now

src/main/java/hhn/labsw/bugageocaching/controller/Controller.java

@@ -335,6 +335,10 @@ public class Controller {
       }
     }
 
+    for(Station station : cache.getStationen()) {
+      stationRepository.delete(station);
+    }
+
     cacheRepository.delete(cache);
 
     return ResponseEntity.status(200).body(new Gson().toJson(true));