Update deploy button with integration, product info (#1158)

### Description

Update the deploy button for Growthbook

Author: AAorris

flags-sdk/growthbook/README.md

@@ -18,7 +18,7 @@ When you create and link a project on Vercel, you may use the [Flags Explorer](h
 
 ## Deploy this template
 
-[![Deploy with Vercel](https://vercel.com/button)](https://vercel.com/new/clone?repository-url=https%3A%2F%2Fgithub.com%2Fvercel%2Fexamples%2Ftree%2Fmain%2Fflags-sdk%2Fgrowthbook&env=GROWTHBOOK_CLIENT_KEY&env=FLAGS_SECRET&envDescription=The+FLAGS_SECRET+will+be+used+by+the+Flags+Explorer+to+securely+overwrite+feature+flags.+Must+be+32+random+bytes%2C+base64-encoded.+Use+the+generated+value+or+set+your+own.&envLink=https%3A%2F%2Fvercel.com%2Fdocs%2Fworkflow-collaboration%2Ffeature-flags%2Fsupporting-feature-flags%23flags_secret-environment-variable&project-name=flags-sdk-growthbook-example&repository-name=flags-sdk-growthbook-example)
+[![Deploy with Vercel](https://vercel.com/button)](https://vercel.com/new/clone?demo-description=Learn%20how%20to%20set%20up%20Growthbook%20flags%20and%20experiments%20using%20Flags%20SDK.&demo-image=%2F%2Fimages.ctfassets.net%2Fe5382hct74si%2F694UbhBteRVZOjb8tIECco%2Fd837767128c0832fa23c87279ab81b3f%2Fopengraph-image.jpg&demo-title=Growthbook%20Flags%20SDK%20Example&demo-url=https%3A%2F%2Fgrowthbook-flags-sdk-example.vercel.app%2F&env=FLAGS_SECRET&envDescription=34%20bytes%20with%20%27base64url%27%20encoding&envLink=https%3A%2F%2Fvercel.com%2Fdocs%2Ffeature-flags%2Fflags-explorer%2Freference%23flags_secret-environment-variable&from=templates&products=%255B%257B%2522type%2522%253A%2522integration%2522%252C%2522protocol%2522%253A%2522experimentation%2522%252C%2522productSlug%2522%253A%2522growthbook%2522%252C%2522integrationSlug%2522%253A%2522growthbook%2522%257D%255D&project-name=Growthbook%20Flags%20SDK%20Example&repository-name=growthbook-flags-sdk-example&repository-url=https%3A%2F%2Fgithub.com%2Fvercel%2Fexamples%2Ftree%2Fmain%2Fflags-sdk%2Fgrowthbook&skippable-integrations=1)
 
 ### Step 1: Link the project