Add Note for missing containerFS metrics

Author: vasireddy99

src/docs/getting-started/container-insights/eks-infra.mdx

@@ -259,4 +259,6 @@ With the above customizations, the final `metric_declarations` will become:
           - pod_cpu_utilization_over_pod_limit
           - pod_memory_utilization_over_pod_limit
 ```  
-This configuration will produce only 4 metrics (rather than 55 metrics as in the default configuration). 
+This configuration will produce only 4 metrics (rather than 55 metrics as in the default configuration).
+
+**Note:** ContainerFS(Container Filesystem) metrics when using the containerd runtime for Amazon EKS or Kubernetes are currently not available, This is a known issue and is being worked on by community contributors. For more information, see [Disk usage metric for containerd](https://github.com/google/cadvisor/issues/2785)