feat: add optgroup to select option

### Prerequisites

- [X] I have read the [Contributing Guidelines](https://github.com/ionic-team/ionic-framework/blob/main/.github/CONTRIBUTING.md#creating-an-issue).
- [X] I agree to follow the [Code of Conduct](https://ionicframework.com/code-of-conduct).
- [X] I have searched for [existing issues](https://github.com/ionic-team/ionic-framework/issues) that already include this feature request, without success.

### Describe the Feature Request

I think is interesting to include ```html ``` tag for ion-select. If is possible I wanna to implement this.

References: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/optgroup

### Describe the Use Case

Use ion-select with optgroup tag, like:

```js
console.log(`ionChange fired with value: ${e.detail.value}`)}
onIonCancel={() => console.log('ionCancel fired')}
onIonDismiss={() => console.log('ionDismiss fired')}
>

Apples
Oranges
Bananas

```

### Describe Preferred Solution

_No response_

### Describe Alternatives

_No response_

### Related Code

_No response_

### Additional Information

_No response_