Use gateway server.AddRoute(), The limit(MaxConns) of this route does not take effect

[jaronnie]

Describe the bug
Use gateway server.AddRoute(), The limit(MaxConns) of this route does not take effect.

To Reproduce

1. The code is

gw := gateway.MustNewServer(c.Gateway)
// gw add api routes
handler.RegisterHandlers(gw.Server, ctx)
gw.Server.AddRoutes(
		[]rest.Route{
			{
				Method:  http.MethodGet,
				Path:    "/api/v1.0/health",
				Handler: HealthHandler(serverCtx),
			},
		},
	)

# MaxConns=100
# 测试 gateway addroute 的路由
hey -z 1s -c 120 -q 1 'http://localhost:8001/api/v1.0/health'
# 测试 api 文件 生成的 handler 注册到 gw server 后的路由

2. The error is

Status code distribution both:
  [200]	120 responses

But origin gateway route take effect

Status code distribution:
  [200]	100 responses
  [503]	20 responses

Expected behavior
expect same responses. All take effect

• origin gateway route
• api handler register to gateway route
• gw server.AddRoute route

Environments (please complete the following information):

• OS: [e.g. Linux]
• go-zero version [1.6.4]
• goctl version [1.6.4]

[jaronnie]

@kevwan

[Issues-translate-bot]

Bot detected the issue body's language is not English, translate it automatically. 👯👭🏻🧑‍🤝‍🧑👫🧑🏿‍🤝‍🧑🏻👩🏾‍🤝‍👨🏿👬🏿

---

@kevwan

[jaronnie]

code example repo: https://github.com/jaronnie/jzero/blob/main/daemon/daemon.go