[BUG][Go Service]Return 404 when there is no component in requesting product/version on localelist/componentlist/supportedlanguagelist APIs.

[lyiyu66]

Describe the bug commit: a3840c9ffc8abf789b0306105e95ce760115c1c6 Return 404 when there is no component in requesting product/version on localelist/componentlist/supportedlanguagelist API. Effected APIs: getting localelist/componentlist/supportedlanguagelist APIs

To Reproduce Steps to reproduce the behavior: Takes component list as example:

1. Go to component list api: GET [/translation/products/{productName}/versions/{version}/componentlist]
2. Request a product&version: no data under product/version folder.
3. Check the response:

   {
   "response": {
   "code": 404,
   "message": "SingleVersionNoData/2.0.0 doesn't exist"
   },
   "data": {
   "components": null,
   "productName": "SingleVersionNoData",
   "version": "2.0.0"
   }
   }

Expected behavior Return to 200 with [] empty list for components item.

[Xiaochao8]

This is an abnormal case and dosn't occure in normal situation, so mark it as low priority.