Use docusaurus-plugin-internaldocs-fb

Summary: Adds a docusaurus plugin to direct fb employees to the internal documentation.

Reviewed By: nikoant

Differential Revision: D21348579

fbshipit-source-id: 5093d68a23ec6ba91c6ae94bf7cb0e58fcf3e7ef

website/docusaurus.config.js

@@ -81,6 +81,7 @@ const siteConfig = {
     '/js/google-analytics.js',
   ],
   stylesheets: [],
+  plugins: ['docusaurus-plugin-internaldocs-fb'],
   presets: [
     [
       '@docusaurus/preset-classic',