Document how to rotate generated secrets

[jandubois]

There is a documentation page for it already: https://github.com/cloudfoundry-incubator/kubecf/blob/master/doc/secret_rotation.md

However, it only documents how to rotate the database encryption key, which is just one subtopic of rotating all the secrets in the cluster.

The rotation of generated secrets will have to be managed by cf-operator, but we need documentation about how to trigger it.

[viovanov]

There should be a script (like a one line) to perform rotation for all secrets all at once.

[viovanov]

Also see the following resources:

https://quarks.suse.dev/docs/quarks-secret/development/#_secretrotation-controller_
https://quarks.suse.dev/docs/quarks-secret/#rotate-credentials

[mook-as]

@jandubois Is this already done by #854? That documented how to rotate a QuarksSecret. It doesn't contain a script to rotate all secrets, though.

[viovanov]

@mook-as I don't think that's enough, and a sample script should be part of this

[mudler]

Can we please avoid to document this inside the kubecf repo, but to https://kubecf.suse.dev/ instead? It sounds more user-facing docs

[mook-as]

Yep, this will be an update to https://github.com/cloudfoundry-incubator/kubecf-docs/blob/master/content/en/docs/Tasks/secrets.md

But to make it reasonable for the user, I'll attempt to make a QuarksJob to automate the rotate-all-secrets case, and tell the user to trigger that instead.