Revert "Update index.js"

This reverts commit 04f5916.

Author: juandjara

src/index.js

@@ -7,7 +7,6 @@ const { pushView } = require('./utils')
 module.exports = async function (req, res) {
   const { pathname, query } = url.parse(req.url, /* parseQueryString */ true)
   res.setHeader('Access-Control-Allow-Origin', '*')
-  res.setHeader("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept")
   // Send all views down if "?all" is true
   if (String(query.all) === 'true') {
     const data = {