MobileComboBox: searchbox should not have aria-expanded property

[majornista]

🐛 Bug Report

🤔 Expected Behavior

aXe DevTools should not throw Elements must only use allowed ARIA attributes.

😯 Current Behavior

aXe DevTools throws Elements must only use allowed ARIA attributes
error because, unlike "combobox", "aria-expanded" is not a valid attribute on "searchbox".

💁 Possible Solution

Remove aria-expanded from searchbox in MobileComboBox.

🌍 Your Environment

Software	Version(s)
react-spectrum	3.24.1
Browser	Chrome
Operating System	macOS

🧢 Your Company/Team

Adobe/Accessibility

🕷 Tracking Issue (optional)

A11Y-5821