[k8s] Define missing roles for entity attributes

[ChrsMark]

Related to #3120

Changes

This PR adds roles for entity attributes that were missing this.

⚠️ Note that for k8s.namespace.name can be an identifying attribute within the scope of a K8s a cluster, hence k8s.namespace.uid is not defined at all nor used in k8sattributes processor of the Collector. I'd love to hear what people think about this and if we should consider introducing the k8s.namespace.uid as an identifying attribute for consistency across k8s resources/entities.

Merge requirement checklist

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