As fixed in pull request #7829 for the ServiceMonitor resource, this is also needed for the PrometheusRule. When
upgrading the ingress-nginx chart in our environment (via Pulumi) from a really old version to the latest (4.2.0) we
noticed it wanted to delete the PrometheusRule resource. This PR should fix that.
* Helpers: Align `ingress-nginx.namespace` to `ingress-nginx.name`.
* Templates: Remove quotes.
In alignment to others. Also does not make sense as `namespace` must conform to DNS.
* Admission Webhooks/Validating Webhook: Make use of `ingress-nginx.namespace`.
* KEDA: Remove comment.
* Templates: Add forgotten namespace definitions.