Update configure-pod-configmap.md

In section 'Use ConfigMap-defined environment variables in Pod commands' - Added command which can be used to show container output

Author: nirajchandak

content/en/docs/tasks/configure-pod-container/configure-pod-configmap.md

@@ -632,7 +632,7 @@ Create that Pod, by running:
 kubectl create -f https://kubernetes.io/examples/pods/pod-configmap-env-var-valueFrom.yaml
 ```
 
-That pod produces the following output from the `test-container` container:
+That pod produces the following output from the `test-container` container (run `kubectl logs dapi-test-pod`):
 
 ```
 very charm