Kubernetes AuthN using IdP

[joshmue]

As a user, I want to access my Kubernetes clusters using identities from my IdP so that RBAC etc. not only applies to ServiceAccounts, but also to users.

Definition of Ready:

• [ ] User Story is small enough to be finished within one sprint
• [ ] User Story is clear and understood by the whole team
• [ ] Acceptance criteria are defined
• [ ] Acceptance criteria are clear and understood by the whole team

Definition of Done:

• [ ] All acceptance criteria are met
• [ ] Changes have been reviewed
• [ ] CI tests have run successfully
• [ ] Documentation has been updated
• [ ] Release Notes have been updated

[joshmue]

I was surprised that I was unable to find an existing issue with this (pretty essential) topic, so I created this one.

[joshmue]

Probably possible via CAPI/Cluster Stacks and some glue. For having a managed experience, see #339.