Request retry test case added

Author: uttamukkoji

lib/core/contentstack-retry.js

@@ -10,7 +10,6 @@ export default function contentstckRetry (axios, defaultOptions, retryLimit = 5,
   })
 
   axios.interceptors.response.use(function (response) {
-    // networkError = 0
     return response
   }, function (error) {
     var wait = retryDelay