Add Deploy to Gatsby Cloud subsection to main tutorial (#24576)
Add Deploy to Gatsby Cloud subsection to main tutorial (#24576)

* Add Gatsby Cloud subsection

* 'Gatsby.js' → 'Gatsby'

* Add more benefits of Gatsby Cloud

* Use straight quotes instead of curly

* Address requested changes

Github → GitHub, add 'shell' to code blocks, relative URLs, make Gatsby Cloud H3 level

* Make Gatsby Cloud H3 level

Co-authored-by: Aisha Blake <e0b0dda0a9e0d5d575159802d44d0f5f5c2978c9@gmail.com>

Co-authored-by: Aisha Blake <e0b0dda0a9e0d5d575159802d44d0f5f5c2978c9@gmail.com>
gatsbyjs/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby