Improve debug output for K8s tests when the pod fails to start

[rdner]

Describe the enhancement:

When a pod fails to start we need to request the most recent logs the pod had before dying.

That would be an equivalent of:

kubectl logs --previous -f --namespace=kube-system $(kubectl get pods --all-namespaces --output=json | jq '.items[].metadata.name' -r | grep elastic-agent)

Describe a specific use case for the enhancement or feature:

Sometimes changes in a Dockerfile lead to a broken entry point for the container, in this case we need to catch the errors of the entry point.

What is the definition of done?

When the container/pod crashes or fails to start we should have an output of the most recent logs as a result of the failed K8s test.

[elasticmachine]

Pinging @elastic/elastic-agent (Team:Elastic-Agent)

[elasticmachine]

Pinging @elastic/elastic-agent-control-plane (Team:Elastic-Agent-Control-Plane)