4.0.0

Breaking changes:

• Use CSS variables for better overwrite experience
• Drop IE11 support
• Drop React 16 support
• Remove the APIs that have deprecation warnings in 3.x
  • progressJumpStep prop is removed

Dev:

• Update bundling tool from Webpack to Vite
• Update Storybook to the latest version and use Vite as well.
• Update testing lib from Enzyme to React Testing Library
• Reactor the code to use React hooks instead of class components