fix(ScrollView): don't report empty visible rect when the content suspends

[alirezamirian]

Closes #8214

✅ Pull Request Checklist:

• [x] Included link to corresponding React Spectrum GitHub Issue.
• [ ] ~~Added/updated unit tests and storybook for this change (for new code or code which already has tests).~~ It requires in-browser testing environment. Let me know if you do have test setup with Cypress, Playwright or other such tools.
• [x] Filled out test instructions.
• [ ] ~~Updated documentation (if it already exists for this component).~~ N/A
• [ ] ~~Looked at the Accessibility Practices for this feature - Aria Practices~~ N/A

📝 Test Instructions:

The reproduction codesandbox link provided in the issue can be used to test the fix..

🧢 Your Project:

https://github.com/alirezamirian/jui