fix: zeebe gateway incorrect rest ingress path

[drodriguez-305]

Which problem does the PR fix?

This change introduced a bug where the ingress path was incorrectly set to include the readiness probe path /actuator/health/readiness. This resulted in the readiness probe path being exposed as an endpoint in the ingress, which inadvertently breaks the intended REST API access.

What's in this PR?

This PR reverts the previous change in ingress-rest.yaml to ensure that only the main service path (ingress.rest.path, e.g., /zeebe) is exposed via the ingress, without appending the readiness probe path.

Checklist

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