[Bug]: Contextual Help does not read body text to screen readers

### Code of conduct

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

### Impacted component(s)

sp-contextual-help

### Expected behavior

When opening the Contextual Help component, the user should be able to navigate and hear aloud the Heading, Body text and Links.

### Actual behavior

When opening the Contextual Help component, the popover body text is not accessible (Voiceover controls do not navigate). In the React version I'm able to jump to the Heading and/or link nested inside. In both the SWC and React versions I'm unable to hear the body text inside the popover.

### Screenshots

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

Chrome

### How can we reproduce this issue?

1. Go to https://opensource.adobe.com/spectrum-web-components/components/contextual-help/#example
2. Click on the "!" icon
3. Popover will open.
4. Voiceover should be able to read aloud the body text.
5. See error

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

_No response_

### Severity

SEV 2

### Logs taken while reproducing problem

_No response_

Start by reproducing the issue in the documented sp-contextual-help example at the linked Contextual Help page using Chrome and VoiceOver. Compare navigation to the Heading, Body text, and Links in the SWC and React versions; done means VoiceOver can navigate to and read the popover body text.

Written by the indexing model from the issue text.