Fix copyright bug

Author: cbeddow

docs/blog/2021-08-01-mdx-blog-post.mdx

@@ -6,7 +6,7 @@ tags: [docusaurus]
 ---
 
 Blog posts support [Docusaurus Markdown features](https://docusaurus.io/docs/markdown-features), such as [MDX](https://mdxjs.com/).
-
+(Facebook, Inc(\.|,)? and its affiliates)|([0-9]{4}-present(\.|,)? Facebook)|([0-9]{4}(\.|,)? Facebook) Copyright
 :::tip
 
 Use the power of React to create interactive blog posts.