fix(observability): fix broken relative link to tutorial in README

The tutorial link was missing the `../` prefix, causing it to resolve
incorrectly from within the observability/ subdirectory.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: Yan Bai

observability/README.md

@@ -14,7 +14,7 @@ Make sure to have:
 
 - A running Kubernetes (K8s) environment with GPUs
   - Run `cd utils && bash install-minikube-cluster.sh`
-  - Or follow our [tutorial](tutorials/00-install-kubernetes-env.md)
+  - Or follow our [tutorial](../tutorials/00-install-kubernetes-env.md)
 
 After that you can run: