Remove or Hide "server" response header on health check port 15021

I am able to remove the server response header on ports 80 and 443 using below EnvoyFilter.

apiVersion: networking.istio.io/v1alpha3
kind: EnvoyFilter
metadata:
  name: remove-server-header
  namespace: istio-system
spec:
  workloadSelector:
    labels:
      istio: ingressgateway
  configPatches:
  - applyTo: NETWORK_FILTER
    match:
      context: GATEWAY
      listener:
        filterChain:
          filter:
            name: "envoy.filters.network.http_connection_manager"
    patch:
      operation: MERGE
      value:
        typed_config:
          "@type": "type.googleapis.com/envoy.extensions.filters.network.http_connection_manager.v3.HttpConnectionManager"
          server_header_transformation: PASS_THROUGH
  - applyTo: ROUTE_CONFIGURATION
    match:
      context: GATEWAY
    patch:
      operation: MERGE
      value:
        response_headers_to_remove:
        - "x-envoy-upstream-service-time"
        - "server"

But I am getting server response header on health check port.

curl -I -X GET  "http://example.com:15021/healthz/ready"
HTTP/1.1 200 OK
date: Wed, 16 Mar 2022 08:48:07 GMT
content-length: 0
x-envoy-upstream-service-time: 0
server: envoy

How to remove it on port 15021?

How to hide "server' response header includes a solution.