Git Command is incorrect

[tfaieta]

Hey, just wanted to point out a small little thing on the readme, thanks for a great template!

Currently on readme.md:

# create a new Gatsby site using the blog starter
npx gatsby new my-blog-starter
https://github.com/hagner/gatsby-starter-blog-mdx

Should be:

# create a new Gatsby site using the blog starter
npx gatsby new my-blog-starter
https://github.com/hagnerd/gatsby-starter-blog-mdx

The issue is a missing 'd' in your username on the git command.