Update gatsby-contentful-plugin README (#38480) (#38607)

* Update gatsby-contentful-plugin README

* Update template link

* Remove line about detailed docs

* chore: trigger build

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Co-authored-by: Nick Taylor <nick@nickyt.co>
Co-authored-by: Florian Kissling <21834+fk@users.noreply.github.com>
(cherry picked from commit 763bfbd)

Co-authored-by: Stephanie Chung <stephanie.chung@netlify.com>

packages/gatsby-source-contentful/README.md

@@ -44,9 +44,7 @@ npm install gatsby-source-contentful gatsby-plugin-image
 
 ## Setup Instructions
 
-To get setup quickly with a new site and have Gatsby Cloud do the heavy lifting, [deploy a new Gatsby Contentful site with just a few clicks on gatsbyjs.com](https://www.gatsbyjs.com/dashboard/deploynow?url=https://github.com/contentful/starter-gatsby-blog).
-
-For more detailed instructions on manually configuring your Gatsby Contentful site for production builds and Preview builds visit [the Gatsby Cloud knowledgebase](https://support.gatsbyjs.com/hc/en-us/articles/360056047134-Add-the-Gatsby-Cloud-App-to-Contentful).
+To get setup quickly with a new site and have Netlify do the heavy lifting, [deploy a new Gatsby Contentful site with just a few clicks on netlify.com](https://app.netlify.com/start/deploy?repository=https://github.com/contentful/starter-gatsby-blog).
 
 ## How to use