Reference: https://github.com/socketio/engine.io-protocol#difference-between-v3-and-v4

Similar to the option of the JS client:

```java
opts = new Socket.Options();
opts.extraHeaders = singletonMap("authorization", singletonList("bearer abcd"));
socket = new Socket(opts);
```

Note: the refactor of the options (similar to [1]) will be done in a
future step.

[1] socketio/engine.io-client@5f47a50

Before this fix, the client could mark the polling transport as open
even though the handshake packet was not received properly (for
example, after a parsing error).

See also: socketio/engine.io-client@1c8cba8