Introduce Storybook to preview React components

[yuya-oc]

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Summary
Introduce Storybook to preview React components. https://storybook.js.org/

We would be able to develop React components without executing/implementing the desktop app. It would be helpful when developing new components in future. And it would work also as the catalog of our React components.

Usage: Open http://localhost:9001/ while executing npm run storybook.

Right now, <Button> is added as a sample. https://794-67276967-gh.circle-artifacts.com/0/storybook/index.html

Issue link
N/A

Test Cases
Storybook app should be generated in CI.

Additional Notes
https://circleci.com/gh/yuya-oc/desktop/794#artifacts > Container 0/storybook/index.html
=> https://794-67276967-gh.circle-artifacts.com/0/storybook/index.html

[jasonblais]

Interesting! This should be a nice improvement, particularly with some of the upcoming end user features.