Description:

Describe the issue.

Today, we enforce that the EnvoyProxy resource must live in the envoy-gateway-system namespace
https://gateway.envoyproxy.io/v1.0.1/tasks/operations/customize-envoyproxy/

This should be loosened

• Some users may want to keep this config in a different namespace, e.g. knative Add envoy gateway testing knative-extensions/net-gateway-api#738
• This resource will have to live in the same namespace as the Gateway once we support attaching EnvoyProxy to Gatways
  in Support attaching EnvoyProxy resource to Gateways #3317

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