add k8s auth doc

doc/SERVING_AUTH_DOCKER.md

@@ -135,7 +135,7 @@ spec:
 其中serviceName就是uci，servicePort就是9393，如果是别的服务就需要改这两个字段，最终会映射到`/foo`下。
 在这一步之后，我们就可以 
 ```
-curl -H "Content-Type:application/json" -X POST -d '{"feed":[{"x": [0.0137, -0.1136, 0.2553, -0.0692, 0.0582, -0.0727, -0.1583, -0.0584, 0.6283, 0.4919, 0.1856, 0.0795, -0.0332]}], "fetch":["price"]}' http://$IP:443/foo/uci/prediction
+curl -H "Content-Type:application/json" -X POST -d '{"feed":[{"x": [0.0137, -0.1136, 0.2553, -0.0692, 0.0582, -0.0727, -0.1583, -0.0584, 0.6283, 0.4919, 0.1856, 0.0795, -0.0332]}], "fetch":["price"]}' http://$IP:$PORT/foo/uci/prediction
 ```
 
 ### Step 4: 增加安全网关限制
@@ -191,7 +191,7 @@ credentials:
 
 执行
 ```
-curl -H "Content-Type:application/json" -H "apikey:ZGVmYXVsdC1hcGlrZXkK" -X POST -d '{"feed":[{"x": [0.0137, -0.1136, 0.2553, -0.0692, 0.0582, -0.0727, -0.1583, -0.0584, 0.6283, 0.4919, 0.1856, 0.0795, -0.0332]}], "fetch":["price"]}' https://10.21.8.133:8521/foo/uci/prediction -k
+curl -H "Content-Type:application/json" -H "apikey:ZGVmYXVsdC1hcGlrZXkK" -X POST -d '{"feed":[{"x": [0.0137, -0.1136, 0.2553, -0.0692, 0.0582, -0.0727, -0.1583, -0.0584, 0.6283, 0.4919, 0.1856, 0.0795, -0.0332]}], "fetch":["price"]}' https://$IP:$PORT/foo/uci/prediction -k
 ```
 我们可以看到 apikey 已经加入到了curl请求的header当中。