Change word in @internationalized/number readme

[o-az]

Great set of tools. Thank you

Arab: person, ethno-linguistic category
Arabic: language

Closes

✅ 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:

🧢 Your Project:

[snowystinger]

Thanks for the PR!

[snowystinger]

could you sign the CLA? you may need to close and reopen the PR after doing that
https://react-spectrum.adobe.com/contribute.html#contributor-license-agreement

[yihuiliao]

closing due to inactivity — i've opened a pr with your changes here #6321

[o-az]

closing due to inactivity — i've opened a pr with your changes here #6321

Thank you