Revert "feat(api): support set-cookie in login/process api"

[BlackHole1]

Reverts #1448

Because:

Access to XMLHttpRequest at 'https://flat-api-dev.whiteboard.agora.io/v1/login/process' from origin 'https://flat-web-dev.whiteboard.agora.io' 
has been blocked by CORS policy: 
Response to preflight request doesn't pass access control check: 
The value of the 'Access-Control-Allow-Origin' header in the response must not be the wildcard '*' when the request's credentials mode is 'include'.
The credentials mode of requests initiated by the XMLHttpRequest is controlled by the withCredentials attribute.