v6.4.0-rc.0

Storybook 6.4 is in RC!! 🎉🎉🎉

• ▶️ Interactive stories to simulate user behavior and tools to debug it
• ⚡️ On-demand architecture for smaller builds and faster load times
• ⛸ Streamlined tooling and documentation for easier upgrades
• 💯 Hundreds more fixes and quality of life improvements

Track the release in the Github: Storybook 6.4 Release 🏗