More accurate readiness check for Pipeline Vertex pods and MonoVertex pods

[whynowy]

Summary

1. There is a readiness check for numa container (introduced in #2014), which checks the health statuses of all the sidecars, this is good enough to tell if the pod is ready or not;
2. There's no readiness check for each sidecar containers today, we need it for better understanding of the sidecar health.

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Message from the maintainers:

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