a4d61a4be4
Noticed when working on https://github.com/ooni/probe/issues/1505. Justification for this diff: 1. [DialEarlyContext calls dialContext with the last argument set to false](https://github.com/lucas-clemente/quic-go/blob/v0.21.1/client.go#L153); 2. [the semantics of the last argument is whether we own the connection](https://github.com/lucas-clemente/quic-go/blob/v0.21.1/client.go#L187); 3. [this value is propagated to the client data structure](https://github.com/lucas-clemente/quic-go/blob/v0.21.1/client.go#L269); 4. [client.dial](https://github.com/lucas-clemente/quic-go/blob/v0.21.1/client.go#L302) runs the session in a background goroutine and only destroys the `packetHandlers` when the connection is owned; 5. [packetHandlerMap.Destroy](https://github.com/lucas-clemente/quic-go/blob/v0.21.1/packet_handler_map.go#L293) closes the underlying PacketConn. 6. also, the documentation clearly states that when you use `DialEarlyContext` you can use the same packet conn multiple times, so it does not take ownership.