accept method
void
accept()
Implementation
void accept(String callerName, String callerNumber, String destinationNumber,
String clientState, String callId, IncomingInviteParams invite,Map<String,String> customHeaders) async {
var sessionId = _selfId;
Session session = await _createSession(null,
peerId: "0", sessionId: sessionId, media: "audio");
_sessions[sessionId] = session;
await session.peerConnection
?.setRemoteDescription(RTCSessionDescription(invite.sdp, "offer"));
_createAnswer(session, "audio", callerName, callerNumber, destinationNumber,
clientState, callId,customHeaders);
onCallStateChange?.call(session, CallState.CallStateNew);
}