Closes #9729 : Added Ghost docs and Bellhops websites to Showcase (#9735)
Closes #9729 : Added Ghost docs and Bellhops websites to Showcase (#9735)

* Closes #9729 : Added Ghost docs and Bellhops websites to Showcase

* Update sites.yml

gatsbyjs/gatsby,ChristopherBiscardi/gatsby,0x80/gatsby,ChristopherBiscardi/gatsby,ChristopherBiscardi/gatsby,gatsbyjs/gatsby,ChristopherBiscardi/gatsby,gatsbyjs/gatsby,0x80/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby,0x80/gatsby,gatsbyjs/gatsby