Bump postcss from 8.4.30 to 8.4.31

Bumps [postcss](https://github.com/postcss/postcss) from 8.4.30 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@8.4.30...8.4.31)

---
updated-dependencies:
- dependency-name: postcss
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

package.json

@@ -39,7 +39,7 @@
         "jquery": "^3.7.1",
         "mini-css-extract-plugin": "^2.7.6",
         "node-sass": "^9.0.0",
-        "postcss": "^8.4.30",
+        "postcss": "^8.4.31",
         "postcss-loader": "^7.3.3",
         "precss": "^4.0.0",
         "sass-loader": "^13.3.2",