[BlockStack] Add id prop to the returned component (#11592)

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### WHY are these changes introduced?

Fixes #11196 <!-- link to issue if one exists -->

<!--
  Context about the problem that’s being addressed.
-->

### WHAT is this pull request doing?
It seems we missed returning the `id` prop when we created the final
element with the React `createElement` API.

```js
export const BlockStack = ({
  as = 'div',
  children,
  align,
  inlineAlign,
  gap,
  id,
  reverseOrder = false,
  ...restProps
}: BlockStackProps) => {
  ...

  return React.createElement(
    as,
    {
      className,
      // Missed the id prop in the final return component
      style: sanitizeCustomProperties(style),
      ...restProps,
    },
    children,
  );
};
```

### 🎩 checklist

- [x] Tested a
[snapshot](https://github.com/Shopify/polaris/blob/main/documentation/Releasing.md#-snapshot-releases)
- [x] Tested on
[mobile](https://github.com/Shopify/polaris/blob/main/documentation/Tophatting.md#cross-browser-testing)
- [x] Tested on [multiple
browsers](https://help.shopify.com/en/manual/shopify-admin/supported-browsers)
- [x] Tested for
[accessibility](https://github.com/Shopify/polaris/blob/main/documentation/Accessibility%20testing.md)
- [x] Updated the component's `README.md` with documentation changes
- [x] [Tophatted
documentation](https://github.com/Shopify/polaris/blob/main/documentation/Tophatting%20documentation.md)
changes in the style guide

.changeset/wild-planets-confess.md

@@ -0,0 +1,5 @@
+---
+'@shopify/polaris': patch
+---
+
+Passed missing `id` prop to the root element of `BlockStack`

polaris-react/src/components/BlockStack/BlockStack.tsx

@@ -76,6 +76,7 @@ export const BlockStack = ({
     as,
     {
       className,
+      id,
       style: sanitizeCustomProperties(style),
       ...restProps,
     },