requestServerSideAccess
Requests server-side access to Play Games Services for the currently signed-in player.
When requested, an authorization code is returned that can be used by your server to exchange for an access token that can be used by your server to access the Play Games Services web APIs.
Parameters
serverClientId
The client ID of the server that will perform the authorization code flow exchange.
forceRefreshToken
If true, when the returned authorization code is exchanged, a refresh token will be included in addition to an access token.