Back out "Merge internal and external troubleshooting pages into one with optional internal-only content"

Summary: Unfortunately optional require does not work with docusaurus bundler configuration in case file not exist, so open source build is failing now. I'm backing out this commit until solution for dynamic imports in docusaurus found.

Reviewed By: mweststrate

Differential Revision: D23679147

fbshipit-source-id: 7934e0a7decf128c1914f52645adaf4617c97eea

website/sidebars.js

@@ -97,7 +97,8 @@ module.exports = {
     ],
   },
   'fb-internal': {
-    'FB Internal': fbInternalOnly([      
+    'FB Internal': fbInternalOnly([
+      'fb/troubleshooting',
       'fb/Add-flipper-to-android-app',
       'fb/Adding-flipper-to-ios-app',
       'fb/LauncherConfig',

website/src/components/FBContent.jsx

@@ -17,9 +17,6 @@ function createElement(createElement) {
   if (React.isValidElement(createElement)) {
     return createElement;
   }
-  if (typeof createElement === 'string') {
-    return createElement;
-  }
   const element = createElement();
   if (React.isValidElement(element)) {
     return element;