chore(deps-dev): bump the postcss group with 1 update (#5362)

Bumps the postcss group with 1 update: [postcss](https://github.com/postcss/postcss).

- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](https://github.com/postcss/postcss/compare/8.4.29...8.4.31)

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

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

package.json

@@ -79,7 +79,7 @@
     "lockfile-lint": "^4.12.1",
     "nodemon": "^3.0.1",
     "npm-run-all": "^4.1.5",
-    "postcss": "^8.4.29",
+    "postcss": "^8.4.31",
     "postcss-cli": "^10.1.0",
     "prettier": "^3.0.3",
     "prettier-plugin-astro": "^0.12.0",