This diff introduces changes to the bidirectional stream gRPC handler to skip session authentication checks by adding the `sessions.skip_authentication` config flag.
In case of the flag was provided we are skipping getting the session parameters from the database and expecting the `device` will be provided as metadata instead. Also, we are creating an empty `SessionItem` instance to provide compatibility with the following code in the handler. We are adding skipping of the changing of "Online" status for the session in case the flag is provided.
Linear task: [[ https://linear.app/comm/issue/ENG-2642/disabling-authentication-mechanism-by-the-config-flag-in-tunnelbroker | ENG-2642 ]]