[corechecks/containerlifecycle] Add owner info to ContainerEvent

[sblumenthal]

What does this PR do?

This PR adds node orchestrator ownership information to the workloadmeta container object, and sends that information up as part of the containerlifecycle container events.

Motivation

We would like to be able to associate containers with the pods which are running them when handling container lifecycle events.

Additional Notes

This is only supported for Kubernetes Pods at the moment, but adding support for other node orchestrators should not require a refactor.

Because the container runtime does not know anything about the node orchestrator which is controlling the container, and because the container events on the container lifecycle side trigger when the container runtime emits the deleted event, we are not able to get the owner information in the event payload that is passed in. As a result of this, I have added a call to pull this information from the global workloadmeta store

Requires DataDog/agent-payload#241

Describe how to test/QA your changes

Like this other PR, testing this is tricky, because (as far as I know) we do not have a way to inspect the payload generated by this check. I was able to validate this locally by building the agent with debug flags set, and then using delve to set breakpoints at the return statements of toPayloadModel and toEventModel in pkg/collector/corechecks/containerlifecycle/event.go. I was able to validate locally that the field is populated this way.

Reviewer's Checklist

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• If applicable, the config template has been updated.

[maycmlee]

Small suggestion