bug: When using service.hosts, the route timeout is invalid

[Donghui0]

Issue description

When using the route to inherit hosts from service feat, the timeout attribute in the route configuration will be invalid.

#4977 (comment)

Environment

• apisix version (cmd: apisix version): 2.10.0
• OS (cmd: uname -a): centos7
• OpenResty / Nginx version (cmd: nginx -V or openresty -V): 1.19.3.1
• etcd version, if have (cmd: run curl http://127.0.0.1:9090/v1/server_info to get the info from server-info API): 3.5

Steps to reproduce

1: create service:
{ "desc":"service-test", "hosts": ["a.xx.com", "b.xx.com"] }
2: create upstream & create route
{ "uri": "/ping", "upstream_id": "${upstream_id}", "service_id": "${step1_resp_service_id}", "timeout": { "connect": 5, "send": 5, "read": 5 } }
3: curl -H "Host: a.xx.com" http://apisix-server:port/ping

The route 5s timeout will be invalid.

Actual result

Will use nginx proxy_(connect/read/send)_timeout as value. such as: 60s.

Error log

none

Expected result

curl 5s timeout. response 504 code.