build(deps): bump polished from 4.1.4 to 4.2.2 in /docs

Bumps [polished](https://github.com/styled-components/polished) from 4.1.4 to 4.2.2.
- [Release notes](https://github.com/styled-components/polished/releases)
- [Commits](styled-components/polished@v4.1.4...v4.2.2)

---
updated-dependencies:
- dependency-name: polished
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

docs/package.json

@@ -36,7 +36,7 @@
     "gatsby-transformer-remark": "^5.13.0",
     "gatsby-transformer-sharp": "^4.13.0",
     "gatsby-transformer-yaml": "^4.13.0",
-    "polished": "^4.1.4",
+    "polished": "^4.2.2",
     "postcss": "^8.4.12",
     "prism-react-renderer": "^1.3.1",
     "prop-types": "^15.8.1",