docs: update README to include emoji for Marketplace link

- Added a shopping bag emoji to the Marketplace link for the Markdown to Telegraph Action to enhance visual appeal.

Author: cyanxiao

README.md

@@ -4,7 +4,7 @@ This README itself is a demo for this action. The [Project GitHub Repo](https://
 
 `md-to-telegraph-action` is a GitHub action that automatically converts markdown files in your repository to pages on [Telegraph](https://telegra.ph/). It is a convenient way to host your documentation on [Telegraph](https://telegra.ph/) without the hassle of setting up a server.
 
-Check it out in Marketplace: [Markdown to Telegraph Action](https://github.com/marketplace/actions/markdown-to-telegraph)
+Check it out in Marketplace 🛍️: [Markdown to Telegraph Action](https://github.com/marketplace/actions/markdown-to-telegraph)
 
 ## Features