Update app platform link from Mu.xyz to Micro

Author: asim

README.md

@@ -4,7 +4,7 @@ Go Micro is a framework for distributed systems development.
 
 **[📖 Documentation](https://go-micro.dev/docs/)** | [Sponsored by Anthropic](https://go-micro.dev/blog/3)
 
-*️⃣ Try [Mu.xyz](https://mu.xyz) - a new app platform by the creator of Go Micro
+*️⃣ Try [Micro](https://micro.mu) - a new app platform by the creator of Go Micro
 
 ## Overview