[bug] ship missing helpers in kubernetes unified rules

[alessandrarizzo]

Background

The Unified Kubernetes ruleset should ship the gcp specific helper as it provides custom extraction for certain k8s rule to work properly.

Changes

Testing

[cursor]

PR Summary

Low Risk
Small pack-manifest change that only adjusts shipped helper dependencies; low likelihood of unintended side effects beyond making previously broken rules work.

Overview
Fixes the PantherManaged.Kubernetes.Unified pack shipping incomplete dependencies by adding panther_event_type_helpers and panther_gcp_helpers to the pack’s global helper list.

This ensures GCP-specific field extraction and event-type utilities are available to the unified Kubernetes detections at runtime.

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