fix: #9239 Focus on the first available option in the dropdown

[jsmitrah]

Closes #9239

✅ 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:

• Configure the component data so that the first 2 or 3 items in the list are disabled.
• Open the component and verify that the initial focus outline snaps straight to the first available option automatically, without needing an extra keypress.

🧢 Your Project: