wordpress proxy with nginx

Error:

Mixed Content: The page at ” was loaded over HTTPS, but requested an insecure stylesheet ”. This request has been blocked; the content must be served over HTTPS.

• install nginx with $IP_ADDRESS:8080

version: '3.1'

services:
  wordpress:
    image: wordpress:6.2.0
    restart: always
    ports:
      - 8080:80
    volumes:
      - ./wordpress:/var/www/html

  db:
    image: mysql:5.7.39
    restart: always
    ports:
      - 3310:3306
    environment:
      MYSQL_ROOT_PASSWORD: root
    volumes:
      - ./mysql:/var/lib/mysql

• Update https://test.example.com inside wordpress admin panel
  

• update wp-config.php
  

define('FORCE_SSL_ADMIN', true);
if ( isset( $_SERVER['HTTP_X_FORWARDED_PROTO'] ) && strpos( $_SERVER['HTTP_X_FORWARDED_PROTO'], 'https') !== false ) {
$_SERVER['HTTPS'] = 'on';
}

• /etc/nginx/conf.d/test.exmaple.conf nginx config

server {
    server_name test.example.com;
    location / {
        proxy_pass http://10.209.229.54:8080/; 
        proxy_http_version 1.1;
        proxy_buffering off;
        proxy_read_timeout    90;
        proxy_connect_timeout 90;
        proxy_redirect        off;
        proxy_set_header Host $host;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-Proto https;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Port 443;
        proxy_set_header Proxy "";
    }

    listen 443 ssl;
    ssl_certificate /etc/nginx/ssl/cert.pem;
    ssl_certificate_key /etc/nginx/ssl/key.pem;

}

server {
    if ($host = test.example.com) {
        return 301 https://$host$request_uri;
    }
    server_name test.example.com;
    listen 80;
    return 404;
}

Reference:

Administration Over SSL