feat(toggle): add required prop (#30156)

Issue number: resolves internal

---------

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## What is the current behavior?
- Currently, the screen reader do not announce the component as required
when `required={true}`.

## What is the new behavior?
- Added a new `required` prop to be used for accessibility purposes that
adds the `required` attribute to toggle's inner native input.

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

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packages/vue/src/proxies.ts

@@ -1016,6 +1016,7 @@ export const IonToggle = /*@__PURE__*/ defineContainer<JSX.IonToggle, JSX.IonTog
   'labelPlacement',
   'justify',
   'alignment',
+  'required',
   'ionChange',
   'ionFocus',
   'ionBlur'