Empty session injected into `$onDisconnect`
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## Information

- **Version:** 7.x
- **Packages**: `@tsed/socketio`

The `@SocketSession` consistently injects an empty Map when invoking the `$onDisconnect` handler. This issue arises due to the utilization of floating promises while invoking the handlers without awaiting the result before destroying the session. To rectify this problem, it is recommended to await the execution of the `$onConnection` and `$onDisconnect` methods.


**Steps to reproduce**:
1. Utilize the `SocketIOModule`.
2. Create a `SocketService` service, implementing the `$onDisconnect` event handler.
3. Inject the session into both `$onDisconnect` and `$onConnection` event handlers using the `@SocketSession`
4. Set something into the session on the `$onConnection`

**Example**

```ts
@SocketService("/room")
export class Room {
  $onConnection(@Socket socket: Socket, @SocketSession session: SocketSession) {
    session.set('id', socket.id);
  }

  $onDisconnect(@SocketSession session: SocketSession) {
    console.log(session.size) // outputs 0
  }
}
```

**Expected result**:
The session must be preserved on the `$onDisconnect`.
