docs(authentication-tutorial): use hello-world stater instead of default (#10690)
docs(authentication-tutorial): use hello-world stater instead of default (#10690)

* docs(authentication-tutorial): use hello-world stater instead of default

* navBar -> nav-bar

ChristopherBiscardi/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby,ChristopherBiscardi/gatsby,gatsbyjs/gatsby,ChristopherBiscardi/gatsby,ChristopherBiscardi/gatsby,gatsbyjs/gatsby