cis-benchmarks won't run offline

[evilnick]

we should document that

[kwmonroe]

Today, I think the procedure would go like this:

---

Use a connected machine to download CIS benchmark configuration data:

wget https://github.com/charmed-kubernetes/kube-bench-config/archive/cis-1.20.zip

Then download the kube-bench application:

wget https://github.com/aquasecurity/kube-bench/releases/download/v0.6.5/kube-bench_0.6.5_linux_amd64.tar.gz

Transfer the above archives to a location that can be accessed by applications in the Charmed Kubernetes deployment. Specify these locations as action parameters when running the benchmark:

juju run-action --wait kubernetes-master/0 cis-benchmark \
    config=http://my_proxy/cis-1.20.zip \
    release=http://my_proxy/kube-bench_0.6.5_linux_amd64.tar.gz

---

In the future, perhaps we could turn these into formal resources that would be attached to charms that include this layer, but that's not on our radar atm.