bug: [1025422] 删除本书阅读引导资源后，书刊权益设置页面接口500

pcloud-service-book/src/main/java/com/pcloud/book/applet/biz/impl/AppletNewsBizImpl.java

@@ -646,7 +646,7 @@ public class AppletNewsBizImpl implements AppletNewsBiz {
         fillBusinessCard(appletNewsDTO);
 
         // 填充城市信息
-        if (StrUtil.isNotBlank(appletNews.getCityCode())) {
+        if (null != appletNews && StrUtil.isNotBlank(appletNews.getCityCode())) {
             appletNewsDTO.setCity(regionMapMapper.getCitysByCode(appletNews.getCityCode()));
         }
         return appletNewsDTO;