fix(typings): fix the type of the "query" option (#1439)

Having type `Object` it was not possible to set values, e.g.:

```ts
if (!this.socket.io.opts.query) {
  this.socket.io.opts.query = {};
}
this.socket.io.opts.query.token = 'abc123';
```

Results in error:

> Element implicitly has an 'any' type because expression of type '"token"' can't be used to index type 'Object'.