fix: 修复远程应用无资产下载xrdp file 500 问题

apps/applications/models/application.py

@@ -288,15 +288,14 @@ class Application(CommonModelMixin, OrgModelMixin, ApplicationTreeNodeMixin):
             raise ValueError("Remote App not has asset attr")
 
     def get_target_ip(self):
+        target_ip = ''
         if self.category_remote_app:
             asset = self.get_remote_app_asset()
-            target_ip = asset.ip
+            target_ip = asset.ip if asset else target_ip
         elif self.category_cloud:
             target_ip = self.attrs.get('cluster')
         elif self.category_db:
             target_ip = self.attrs.get('host')
-        else:
-            target_ip = ''
         return target_ip