Fix compiler error (#453)

Author: etimr

srv/admin-service.cds

@@ -5,6 +5,7 @@ using {my.common.Hierarchy as Hierarchy} from './hierarchy';
 using {sap.attachments.Attachments} from 'com.sap.cds/cds-feature-attachments';
 
 extend my.Orders with changelog.changeTracked;
+extend my.Genres with Hierarchy;
 
 @path: 'admin'
 @odata.apply.transformations
@@ -20,7 +21,6 @@ service AdminService @(requires: 'admin') {
 
   entity Authors        as projection on my.Authors;
   entity Orders         as select from my.Orders;
-  extend my.Genres with Hierarchy;
 
   type NextSibling : cuid { };
   entity GenreHierarchy as projection on my.Genres

srv/cat-service.cds

@@ -1,5 +1,4 @@
 using {my.bookshop as my} from '../db/index';
-using {my.common.Hierarchy as Hierarchy} from './hierarchy';
 
 @path : 'browse'
 @odata.apply.transformations
@@ -17,8 +16,6 @@ service CatalogService @(requires: 'any') {
 
     @readonly
     entity Reviews     as projection on my.Reviews;
-
-    extend my.Genres with Hierarchy;
     @readonly
     entity GenreHierarchy as projection on my.Genres;