When using the GatewayNamespace mode, if you create a Gateway and there is already a Service or Deployment with the same name in the same namespace, the Gateway will be in an abnormal state.

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*Description*:
When using the GatewayNamespace mode, if you create a Gateway and there is already a Service or Deployment with the same name in the same namespace, the Gateway will be in an abnormal state.

*Repro steps*:
1. An nginx instance has been created in the default namespace.
2. Create a gateway.
apiVersion: gateway.networking.k8s.io/v1
kind: Gateway
metadata:
name: nginx
namespace: default
spec:
gatewayClassName: envoy-gateway
listeners:
- name: http
protocol: HTTP
port: 80

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*Environment*:
>Include the environment like gateway version, envoy version and so on.
1.7.2

*Logs*:
>Include the access logs and the Envoy logs.
observed an error {"runner": "infrastructure", "error": "failed to create or update deployment default/nginx: an illegal change in a custom label of EnvoyProxy is detected when updating default/nginx. The custom label config of deployment in EnvoyProxy, which is initiated with the envoy gateway of v1.1 or earlier, is immutable. Please recreate an envoy proxy with a new custom label if you need to change the custom label. This issue won't happen with the envoy proxy resource initialized by the envoygateway v1.2 or later"}