refactor: remove unused line

In Socket.IO v2, the Socket `query` option was sent when connecting to
a custom namespace (but not for the main namespace).

This was fixed in Socket.IO v3 ([1]), so this line is now useless.

[1]: https://socket.io/docs/v3/migrating-from-2-x-to-3-0/#Add-a-clear-distinction-between-the-Manager-query-option-and-the-Socket-query-option

lib/manager.ts

@@ -631,7 +631,6 @@ export class Manager extends Emitter {
    */
   _packet(packet: Partial<Packet & { query: string; options: any }>) {
     debug("writing packet %j", packet);
-    if (packet.query && packet.type === 0) packet.nsp += "?" + packet.query;
 
     const encodedPackets = this.encoder.encode(packet as Packet);
     for (let i = 0; i < encodedPackets.length; i++) {