orchestrator-kubernetes: Remove TODO about owner_references

[def-]

I'm not sure if more has to be done to actually set the correct values. @pH14 @benesch Can you please check?

Follow-up to #29614

Checklist

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[benesch]

Hmm. I don't think "no owner references" is what the TODO intended. I assume the "correct" owner reference is the Environment resource. But that's actually itself a design flaw, because we want the VPC endpoints to persist even if the environment is deprovisioned/reprovisioned, or migrated between Kubernetes clusters.

Also, the owner references here also don't really matter, because the VPC endpoints get created in the environment namespace, and everything inside that namespace gets deleted when the namespace gets deleted.

I'm inclined to just delete the TODO and move on. @pH14 or @alex-hunt-materialize team would know better if there's some reason it's important to have an owner reference here, vs just relying on namespace deletion.

[alex-hunt-materialize]

For now, we should just leave it without owner references, and let the namespace deletion clean them up.

Long-term, we want to move these outside the individual environment clusters, so they may persist for the lifetime of the EnvironmentAssignment, not of the Environment. That would allow us to soft-delete and restore, and to migrate across environment clusters without breaking their privatelink.

[benesch]

Great—@def- I think we can just eliminate the TODO and the commented out code entirely then.

[benesch]

Thank you!