Upgraded to eslint 6 and fixed barrel file issue for codeclimate (#7161)

.codeclimate.yml

@@ -48,7 +48,9 @@ plugins:
     enabled: true
   eslint:
     enabled: true
-    channel: "eslint-5"
+    channel: "eslint-6"
+    exclude_patterns:
+      - "app/javascript/**/index.js" # exclude barrel files
   duplication:
     enabled: true
     config:
@@ -71,4 +73,3 @@ exclude_patterns:
   - "**/.eslintrc.js"
   - "*.js"
   - "**/__stories__/"
-

app/assets/javascripts/initializers/initializeBaseUserData.js

@@ -1,6 +1,6 @@
 'use strict';
 
-/* global userData, filterXSS */
+/* global filterXSS */
 
 function initializeUserProfileContent(user) {
   document.getElementById('sidebar-profile--avatar').src = user.profile_image_90;