chore: Remove unused RBAC permission for product role

[NickLarsenNZ]

Part of stackabletech/issues#798

Follow up of https://github.com/stackabletech/airflow-operator/pull/767/changes#r3014650545

Details

The events rule in the product ClusterRole (lines 31-38) looks safe to remove. Here's why:

1. Airflow does not publish Kubernetes events. No Airflow component (scheduler, webserver, worker, etc.) calls create_namespaced_event or uses EventsV1Api to create Event objects.
2. Airflow only reads events, optionally. The KubernetesPodOperator can read events for failed pods via CoreV1Api.list_namespaced_event (core "" API group, not events.k8s.io), and even that is off by default in the official Airflow Helm chart.
3. The comment is inaccurate. "Airflow components publish Kubernetes events" - they don't. The operator publishes events (that's correctly handled in clusterrole-operator.yaml), but the workload pods don't.
4. The official Airflow Helm chart only grants get/list on core API events, and makes even that optional (rbac.events = false by default).

[razvan]

maybe also update the pr list in the changelog ?

[NickLarsenNZ]

maybe also update the pr list in the changelog ?

Oops, yeah I had that sitting here locally.

[razvan]

nice