docs: Update README with link to Taskchampion sync server

Added a link to the official Taskchampion sync server image in the README.

Author: its-me-abhishek

README.md

@@ -95,7 +95,7 @@ CCSync is composed of **three core modules**:
 
 1. **Backend** — The REST API and logic layer that communicates with Taskwarrior clients.
 2. **Web Frontend** — A modern web UI that stores and manages tasks in-browser.
-3. **Taskchampion Sync Server** — In order to sync tasks with you Taskwarrior instances, CCSync by default uses the offical Taskchampion sync server image to sync tasks.
+3. **Taskchampion Sync Server** — In order to sync tasks with you Taskwarrior instances, CCSync by default uses the offical [Taskchampion sync server image](https://github.com/GothenburgBitFactory/taskchampion-sync-server) to sync tasks.
 
 📖 Learn more in the [official documentation](https://its-me-abhishek.github.io/ccsync-docs/).