Remove irrelevant content from README (#25)

This section is included in Starlight’s initial README for a developer to quickly deploy a project, and shouldn’t be included in a project that already has a deployment.

Author: lianghai

README.md

@@ -2,21 +2,8 @@
 
 This is the source for <https://icu4x.unicode.org/>
 
-## Starlight Starter Kit: Basics
-
 [![Built with Starlight](https://astro.badg.es/v2/built-with-starlight/tiny.svg)](https://starlight.astro.build)
 
-```
-npm create astro@latest -- --template starlight
-```
-
-[![Open in StackBlitz](https://developer.stackblitz.com/img/open_in_stackblitz.svg)](https://stackblitz.com/github/withastro/starlight/tree/main/examples/basics)
-[![Open with CodeSandbox](https://assets.codesandbox.io/github/button-edit-lime.svg)](https://codesandbox.io/p/sandbox/github/withastro/starlight/tree/main/examples/basics)
-[![Deploy to Netlify](https://www.netlify.com/img/deploy/button.svg)](https://app.netlify.com/start/deploy?repository=https://github.com/withastro/starlight&create_from_path=examples/basics)
-[![Deploy with Vercel](https://vercel.com/button)](https://vercel.com/new/clone?repository-url=https%3A%2F%2Fgithub.com%2Fwithastro%2Fstarlight%2Ftree%2Fmain%2Fexamples%2Fbasics&project-name=my-starlight-docs&repository-name=my-starlight-docs)
-
-> 🧑‍🚀 **Seasoned astronaut?** Delete this file. Have fun!
-
 ## 🚀 Project Structure
 
 Inside of your Astro + Starlight project, you'll see the following folders and files: