Update server.js (#10056)
Update server.js (#10056)

I think `httpOnly` property should set as `cookie`'s property.
This is because `SessionOptions` is following.

```
  interface SessionOptions {
    secret: string | string[];
    name?: string;
    store?: Store | MemoryStore;
    cookie?: {
      maxAge?: number;
      signed?: boolean;
      expires?: Date;
      httpOnly?: boolean;
      path?: string;
      domain?: string;
      secure?: boolean | 'auto';
      encode?: (val: string) => string;
      sameSite?: boolean | 'lax' | 'strict' | 'none';
    };
    genid?(req: express.Request): string;
    rolling?: boolean;
    resave?: boolean;
    proxy?: boolean;
    saveUninitialized?: boolean;
    unset?: string;
  }
```
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