chore: bump @storybook/react from 6.3.12 to 6.4.18 in /site (#172)

Bumps [@storybook/react](https://github.com/storybookjs/storybook/tree/HEAD/app/react) from 6.3.12 to 6.4.18.
- [Release notes](https://github.com/storybookjs/storybook/releases)
- [Changelog](https://github.com/storybookjs/storybook/blob/next/CHANGELOG.md)
- [Commits](https://github.com/storybookjs/storybook/commits/v6.4.18/app/react)

---
updated-dependencies:
- dependency-name: "@storybook/react"
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

site/package.json

@@ -25,7 +25,7 @@
     "@storybook/addon-actions": "6.3.12",
     "@storybook/addon-essentials": "6.3.12",
     "@storybook/addon-links": "6.3.12",
-    "@storybook/react": "6.3.12",
+    "@storybook/react": "6.4.18",
     "@testing-library/react": "12.1.2",
     "@types/express": "4.17.13",
     "@types/jest": "27.4.0",