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

Co-authored-by: Pavel Valodzka <pavel@valodzka.name>

Bumps [engine.io](https://github.com/socketio/engine.io) from 4.0.5 to 4.1.2.
- [Release notes](https://github.com/socketio/engine.io/releases)
- [Changelog](https://github.com/socketio/engine.io/blob/4.1.2/CHANGELOG.md)
- [Commits](socketio/engine.io@4.0.5...4.1.2)

---
updated-dependencies:
- dependency-name: engine.io
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

With the previous value (10 seconds by default), a connection
established with HTTP long-polling was closed if the server did not
send any packet for 10 seconds (the HTTP request would timeout from the
client side).

It will now default to 1 minute, which is above the
`pingInterval + pingTimeout` value from the server.

Note: the connectTimeout and writeTimeout options are left as is (10
seconds), but you may need to increase them depending on your use case:

```
OkHttpClient client = new OkHttpClient.Builder()
	.connectTimeout(20, TimeUnit.SECONDS)
	.readTimeout(1, TimeUnit.MINUTES)
	.writeTimeout(1, TimeUnit.MINUTES)
        .build();
```

Related:

- socketio/socket.io-client-java#491
- socketio/socket.io-client-java#660

Maven has been upgraded from 3.8 to 3.9, which is not compatible with JDK 7.

See also: actions/runner-images#11093

Previous version is no longer available at [1].

[1]: https://dlcdn.apache.org/maven/maven-3/