Tidy up license headers

Summary: Changelog: Tidy up license headers

Reviewed By: SidharthGuglani

Differential Revision: D17919414

fbshipit-source-id: 0501b495dc0a42256ca6ba3284a873da1ab175c0

website/src/components/Playground/webpack.config.js

@@ -1,3 +1,10 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
 const path = require('path');
 const MiniCssExtractPlugin = require('mini-css-extract-plugin');
 

website/src/pages/docs/index.css

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  */
- 
+
 .docs-landing .heading {
   padding-top: 50px;
   padding-bottom: 50px;