Merge branch 'disable_content_base' into 'master'

Disable un-needed contentBase for webpack-dev-server

See merge request gitlab-org/gitlab!41841

config/webpack.config.js

@@ -547,6 +547,7 @@ module.exports = {
       'Access-Control-Allow-Origin': '*',
       'Access-Control-Allow-Headers': '*',
     },
+    contentBase: false,
     stats: 'errors-only',
     hot: DEV_SERVER_LIVERELOAD,
     inline: DEV_SERVER_LIVERELOAD,