fix(ci): 前端容器改为 Dockerfile 镜像打包，去除宿主机路径挂载依赖

docker-compose.yml

@@ -8,11 +8,8 @@ services:
       - "8089:8080"
 
   frontend:
-    image: nginx:alpine
+    build: ./frontend
     container_name: blog-frontend
     restart: always
     ports:
       - "8088:80"
-    volumes:
-      - ./frontend:/usr/share/nginx/html
-      - ./frontend/nginx.conf:/etc/nginx/conf.d/default.conf:ro

frontend/Dockerfile

@@ -0,0 +1,5 @@
+FROM nginx:alpine
+COPY index.html /usr/share/nginx/html/index.html
+COPY nginx.conf /etc/nginx/conf.d/default.conf
+EXPOSE 80
+CMD ["nginx", "-g", "daemon off;"]