Bump ejs and @storybook/react

Removes [ejs](https://github.com/mde/ejs). It's no longer used after updating ancestor dependency [@storybook/react](https://github.com/storybookjs/storybook/tree/HEAD/app/react). These dependencies need to be updated together.


Removes `ejs`

Updates `@storybook/react` from 5.0.6 to 6.5.15
- [Release notes](https://github.com/storybookjs/storybook/releases)
- [Changelog](https://github.com/storybookjs/storybook/blob/v6.5.15/CHANGELOG.md)
- [Commits](https://github.com/storybookjs/storybook/commits/v6.5.15/app/react)

---
updated-dependencies:
- dependency-name: ejs
  dependency-type: indirect
- dependency-name: "@storybook/react"
  dependency-type: direct:development
...

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