feat: allow route to inherit hosts from service

[spacewander]

Signed-off-by: spacewander spacewanderlzx@gmail.com

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[Donghui0]

in plugin.merge_service_route function, need to add processing for route.value.timeout. Otherwise, the timeout attribute of ApisixRoute will be invalid.

I have a question in the merge service_route method. Why not directly core.table.deepcopy(route_conf), assign the attribute of service to new_conf ?