Bump postcss from 8.4.24 to 8.4.31

Bumps [postcss](https://github.com/postcss/postcss) from 8.4.24 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@8.4.24...8.4.31)

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

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

package.json

@@ -42,7 +42,7 @@
     "html-loader": "4.2.0",
     "html-webpack-plugin": "5.5.3",
     "mini-css-extract-plugin": "2.7.6",
-    "postcss": "8.4.24",
+    "postcss": "8.4.31",
     "postcss-loader": "7.3.3",
     "postcss-preset-env": "8.4.1",
     "postcss-scss": "4.0.6",