ActionGroup's `summaryIcon` should change icon regardless `selectionMode`

### Provide a general summary of the feature here

1. Take `ActionGroup#Collapsing behavior#Selection` example ([link](https://react-spectrum.adobe.com/react-spectrum/ActionGroup.html#selection-1)).
2. Set `selectionMode` to `none`.

```ts
import TextStyle from '@spectrum-icons/workflow/TextStyle';

}
maxWidth={100}>


Bold



Italic



Underline



Strikethrough

```

### 🤔 Expected Behavior?

Icon is as specified by `selectionMode` (`TextStyle` in our example).

### 😯 Current Behavior

Icon switches back from specified `TextStyle` to default dot-dot-dot one.

### 💁 Possible Solution

_No response_

### 🔦 Context

Although it is mentioned in the doc:
> The icon displayed in the dropdown menu button when a **_selectable_** ActionGroup is collapsed.

I personally see no reason why the icon cannot be changed with `selectionMode` set to `none`. Such `ActionGroup`s are commonly used as a controlled element for menus.

### 💻 Examples

_No response_

### 🧢 Your Company/Team

_No response_

### 🕷 Tracking Issue

_No response_