build(deps): bump postcss from 8.4.21 to 8.4.31

Bumps [postcss](https://github.com/postcss/postcss) from 8.4.21 to 8.4.31.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@8.4.21...8.4.31)

---
updated-dependencies:
- dependency-name: postcss
  dependency-type: direct:production
...

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

package.json

@@ -35,7 +35,7 @@
 		"core-js": "^3.29.1",
 		"css-vars-ponyfill": "^2.3.2",
 		"ky": "^0.33.3",
-		"postcss": "^8.4.21",
+		"postcss": "^8.4.31",
 		"postcss-calc": "^8.0",
 		"postcss-cli": "^10.1.0",
 		"postcss-preset-env": "^8.0.1",