peers
fix: send OPEN message when client reconnects
There are cases where the open event does not fire when calling peer.reconnect() on the client.
If the socket with the client is connected after the client information has been removed from the server, there is no issue.
However, if a new socket is connected due to a reconnect before the client information is removed from the server, the MessageType.OPEN is not sent, causing the client to fail in receiving the open event.
Therefore, I modified it so that MessageType.OPEN is sent even when the client exists, when the _onSocketConnection() of the new socket is called.
For reference, there is an issue posted in the PeerJS repo by someone who experienced the same problem as I did. https://github.com/peers/peerjs/issues/1289
