[Bug]: Checkbox.checked property no longer defined

### Code of conduct

- [x] I agree to follow this project's code of conduct.

### Impacted component(s)

@spectrum-web-components/checkbox

### Library version

1.10.0

### Expected behavior

In the latest version of the Checkbox component, the Checkbox.checked property is missing.
const checkbox:Checkbox =....;

console.log(checkbox.checked);

### Actual behavior

checked is not defined

### Screenshots

_No response_

### What browsers are you seeing the problem in?

_No response_

### How can we reproduce this issue?

Have code that uses the Checkbox.checked property

private async onChangeLocalizationAsync(evt: Event){
const checkbox = evt.currentTarget as Checkbox;

if (checkbox.checked){
}
}

### Sample code or abstract reproduction which illustrates the problem

_No response_

### Severity

None

### Logs taken while reproducing problem

_No response_

### Would you like to track this issue in Jira?

- [x] Yes, please tell me the ticket number!

Start with the @spectrum-web-components/checkbox component entry point and reproduce the TypeScript access shown in the issue. Check why Checkbox.checked is not defined in version 1.10.0; done means the property is available and the onChangeLocalizationAsync example can read it.

Written by the indexing model from the issue text.