DatePicker with defaultValue persists time zone

[boutahlilsoufiane]

Closes #6005

✅ Pull Request Checklist:

• [x] Included link to corresponding React Spectrum GitHub Issue.
• [X] 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]

Looks like you might need to sign the CLA? https://react-spectrum.adobe.com/contribute.html#contributor-license-agreement

[boutahlilsoufiane]

@snowystinger thanks for the review, I have just signed the CLA.

[snowystinger]

Thank, I'll close and reopen as it looks like it's stuck at the moment.

[snowystinger]

trying again to get it unstuck