Fix clean vendoring of repo for enabling plugin implementations

[tssurya]

• [ ] document how it needs to be done
• [x] should we be vendoring in the config part of the repo as well? -> I'd say yes rather than letting each plugin generate their own yamls, we should be using the kustomization.yaml uniformly
• [x] If kustomization.yaml isn't used and plugins directly generate yamls it will break them at install time since the api-approved annotation will be missing.

These are some issues that we ran into when doing OVNK implementation for making the controller install CRD, so we should certainly clarify these.

I am waiting for the clientget changes to land first to try the vendoring again since there is some reordering of repos as a result of that.

[tssurya]

/assign @tssurya

[tssurya]

Spoke about this with @astoycos ; we agreed to do an approach similar to what gateway-api does: https://gateway-api.sigs.k8s.io/guides/#installing-gateway-api

When we cut a release, folks can then just point to our released version and do an apply of the crd in their cluster.

[tssurya]

/unassign @tssurya /assign @Dyanngg