refactored exceptions

SchengenVisaApi/ApplicationLayer/Services/GeneralExceptions/EntityUsedInDatabaseException.cs

@@ -1,7 +0,0 @@
-using ApplicationLayer.GeneralExceptions;
-
-namespace ApplicationLayer.Services.GeneralExceptions
-{
-    /// Exception to throw when can't complete some action on entity(delete or something) because it's needed for other entities
-    public class EntityUsedInDatabaseException(string message) : ApiException(message);
-}