Support new Kubernetes PodSecurityStandards for Korifi core pods

[danail-branekov]

As of Kubernetes 1.21 pod security policies are deprecated and are going to be removed in 1.25. They are going to be replaced by the Pod security admission controller and pod security standards. This means that pod security is going to be configured per namespace rather than per pod.

We would like to enforce the restricted security standard on Korifi "core" pods

Accceptance

Given Korifi is deployed
Then I see that the eirini-controller korifi-api-system, korifi-controllers-system and korifi-kpack-build-system namespace contains the following labels:

pod-security.kubernetes.io/audit=restricted
pod-security.kubernetes.io/enforce=restricted

When Korifi is deployed
Then The containers of the eirini-controller,korifi-api-system, korifi-controllers-system and korifi-kpack-build-system pods have the following security context:

securityContext:
  allowPrivilegeEscalation: false
  capabilities:
    drop:
      - ALL
  runAsNonRoot: true
  seccompProfile:
    type: RuntimeDefault

• Enforce the restricted pod security on Korifi's pods/namespaces: PR Configure Korifi with restricted pod-security #1277
• Enforce the restricted pod security on eirini-controllers pods/namespaces
• Release a new version of eirini-controller
• Bump the eirini-controller version in install-dependencies