feat: add AnnouncementController#resetIsShownStates

[digiwand]

Explanation

Adds a method in the AnnouncementController to support the new Developer Options Settings Page → Reset State → What's New Announcements

References

Partially Fixes: https://github.com/MetaMask/metamask-extension/issues/23592 Blocks: https://github.com/MetaMask/metamask-extension/pull/22382

Changelog

@metamask/announcement-controller

• Feat: Add resetIsShownStates method

Checklist

• [ ] I've updated the test suite for new or updated code as appropriate
• [ ] I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• [ ] I've highlighted breaking changes using the "BREAKING" category above as appropriate