[docs] Add noopener/noreferrer to window.open example

# [docs] Add noopener/noreferrer to window.open example

## Summary

The social verification guide includes a `window.open(..., '_blank')` example without `noopener` or `noreferrer`.

## Affected file

- `docs/base-account/guides/verify-social-accounts.mdx`
- Line 431

## Current code

```js
window.open(deepLink, '_blank')
```

## Suggested code

```js
window.open(deepLink, '_blank', 'noopener,noreferrer')
```

## Why this matters

When opening a new browsing context, explicitly using `noopener` helps prevent the opened page from gaining access to the opener context. This makes the docs example safer for developers to copy into production apps.