docs(kubernetes.md): generalize namespace in kubectl command example

The kubectl command example in the documentation has been updated to use a placeholder for the namespace (`<namespace>`) instead of a specific namespace (`cb-core`). This change makes the documentation more generic and useful for users who need to apply the command to different namespaces.

azure/kubernetes.md

@@ -24,4 +24,4 @@ Lens is an IDE built specifically for Kubernetes that lets you connect to cluste
 
 ### Restart all deployments
 
-    kubectl rollout restart deployment -n cb-core
+    kubectl rollout restart deployment -n <namespace>