Removed HTML boilerplate from examples folder to simplify build script

examples/index.html

@@ -1,3 +0,0 @@
-<div id="root">
-  <!-- This div's content will be managed by React. -->
-</div>

gatsby-node.js

@@ -168,11 +168,8 @@ exports.createPages = async ({graphql, boundActionCreators}) => {
   });
 
   // Create Codepen example pages
-  const htmlTemplate = fs.readFileSync('./examples/index.html', 'utf8');
   fs.readdirSync('./examples').forEach(file => {
-    // Only create pages for the JS files
-    if (file.endsWith('.js')) {
-      const slug = file.substring(0, file.length - 3);
+    const slug = file.substring(0, file.length - 3); // Trim extension
     const jsTemplate = fs.readFileSync(`./examples/${file}`, 'utf8');
 
     createPage({
@@ -181,12 +178,11 @@ exports.createPages = async ({graphql, boundActionCreators}) => {
       context: {
         slug,
         payload: {
-            html: htmlTemplate,
+          html: '<div id="root"></div>',
           js: jsTemplate,
         },
       },
     });
-    }
   });
 };