Wrong image registry for section '12 - Deploy a standalone application' (liveness command example)

mopak

The example in 12 section 'Deploy a standalone application' for liveness command is outdated:

https://trainingportal.linuxfoundation.org/learn/course/introduction-to-kubernetes/deploying-a-standalone-application/deploying-a-standalone-application?page=14

image: k8s.gcr.io/busybox

k8s.gcr.io as an Artifactory storage is closed, we can use official Docker image hub or other alternative.

It will be also good to update in the example.