Documentation to run kube-bench on AKS is outdated

[oliviergaumond]

The documentation provided here https://github.com/aquasecurity/kube-bench/blob/main/docs/running.md#running-in-an-aks-cluster to run kube-bench as a container on one of the AKS node is not working.

It uses docker cli command, but since Kubernetes 1.19 AKS uses containerd instead of docker as the container runtime. Thus the docker cli is not installed on the nodes ensuing in the following error message
Command 'docker' not found

Maybe we should adapt the documentation to recommend using the job.yaml file to run kube-bench as a one-time job?