feat: #8007 ComboBox Autofocus on First List item when ListBox is filtered

[jsmitrah]

Closes #8007

✅ Pull Request Checklist:

• 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).
• Filled out test instructions.
• Updated documentation (if it already exists for this component).
• Looked at the Accessibility Practices for this feature - Aria Practices

📝 Test Instructions:

• Use the ComboBox with multiple options.
• Search for a particular option; the option will be autofocused.

🧢 Your Project:

[LFDanLu]

@jsmitrah just curious, but have you tested this behavior with various screenreaders yet? The main reason this wasn't implemented as default behavior was issues with NVDA in Firefox where the user would no longer get notifications of where the text cursor was being moved via Left/Right Arrow if a item was being focused in the menu, so we'll want to double check that and do a full sweep across other screen readers as behavior may have drifted since then